Python Introduction_01_2020_in_class.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Python Introduction with some detours\n",
    "![Python](https://www.python.org/static/community_logos/python-logo-generic.svg)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "![xkcd](https://imgs.xkcd.com/comics/python.png)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Table of Contents <a class=\"anchor\" id=\"toc\">\n",
    "\n",
    "* [Hello World](#hello-world)\n",
    "* [Python History](#python-history)\n",
    "* [What is Programming?](#what-is-programming)\n",
    "* [Jupyter Basics](#jupyter-basics)\n",
    "* [Variables](#variables)\n",
    "* [Arithmetic](#arithmetic)\n",
    "* [Program Flow Control](#flow-control)\n",
    "* [Functions](#functions)\n",
    "* [Libraries](#libraries)\n",
    "* [Crucial Python Ideas](#python-ideas)\n",
    "* [Learning Resources](#learning-resources)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Hello World <a class=\"anchor\" id=\"hello-world\">\n",
    "    \n",
    "   [Back to Table of Contents](#toc)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello Accenture!\n",
      "Nice day for a walk, isn't it? Nothing clean?\n"
     ]
    }
   ],
   "source": [
    "print(\"Hello Accenture!\")\n",
    "print(\"Nice day for a walk, isn't it? Nothing clean?\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {},
   "outputs": [],
   "source": [
    "myname = \"Valdis\""
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Voldemorts\n"
     ]
    }
   ],
   "source": [
    "myname = \"Voldemorts\"\n",
    "print(myname)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Valdis\n"
     ]
    }
   ],
   "source": [
    "print(myname)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "str"
      ]
     },
     "execution_count": 17,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "type(myname)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "### Try printing a greeting of your own!"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [],
   "source": [
    "### What Happens when you get an error?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello world\n",
      "Another Hello\n"
     ]
    }
   ],
   "source": [
    "print(\"Hello world\")\n",
    "print(\"Another Hello\")\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {
    "scrolled": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello world!\n"
     ]
    }
   ],
   "source": [
    "print(\"Hello world!\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Something\n",
      "Another printing\n"
     ]
    }
   ],
   "source": [
    "# My big comment\n",
    "print(\"Something\")\n",
    "# another comment\n",
    "print(\"Another printing\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "### Try printing a greeting of your own!"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "### What Happens when you get an error?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello world\n",
      "Another Hello\n"
     ]
    }
   ],
   "source": [
    "print(\"Hello world\")\n",
    "print(\"Another Hello\")\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Python History <a class=\"anchor\" id=\"python-history\">\n",
    "    \n",
    "[Back to Table of Contents](#toc)\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Python created by Guido von Rossum in early 1990s  (later at Google,Dropbox)\n",
    "## Language reference: https://docs.python.org/3/index.html\n",
    "\n",
    "![Guido](https://upload.wikimedia.org/wikipedia/commons/thumb/d/d0/Guido-portrait-2014-curvves.jpg/290px-Guido-portrait-2014-curvves.jpg)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Why Python? "
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Why Python but not Julia or R or some other language or even VBA in Excel?\n",
    "### Readability, Glue Language(APIs), From Startups to Google and Facebook, Pipeline\n",
    "\n",
    "Prime numbers in J language used at some finance institutions **1: I. 2= +/ 0= (] |/ ]) i.y**"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "![Python](img/python_growth.png)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Python is now programming language # 3 in TIOBE language index (as of September 2018)\n",
    "https://www.tiobe.com/tiobe-index/\n",
    "\n",
    "https://developers.slashdot.org/story/18/09/08/1722213/python-displaces-c-in-tiobe-index-top-3"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "![Anaconda](https://www.anaconda.com/wp-content/uploads/2018/06/cropped-Anaconda_horizontal_RGB-1-600x102.png)\n",
    "https://www.anaconda.com/download/"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Batteries included principle\n",
    "![Batteries](img/batteries.jpg)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## What is Programming? <a class=\"anchor\" id=\"what-is-programming\">\n",
    "    \n",
    "[Back to Table of Contents](#toc)\n",
    "\n",
    "* Egg algorithm\n",
    "* Computers are stupid, they only do what they are told to do\n",
    "* If it is stupid but it works, then it is not stupid\n",
    "* Make it work, make it right, make it fast(last two steps often not required in real life)\n",
    "* GIGO principle\n",
    "\n",
    "* Error messages are nothing to be afraid of, usually the message will explain what needs fixing!"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Our first comment\n",
    "# Real Program Comments should generally describe why\n",
    "# Here  comments will describe extra information not covered or needed for starting out\n",
    "# REPL(Read,Eval,Print, Loop) \n",
    "# Python - Interpreted Language(commands executed as they come)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Jupyter Basics <a class=\"anchor\" id=\"jupyter-basics\">\n",
    "    \n",
    "[Back to Table of Contents](#toc)\n",
    "\n",
    "\n",
    "* Esc-M turns cell into Markdown cell for formatting (https://guides.github.com/pdfs/markdown-cheatsheet-online.pdf)\n",
    "* Esc-Y turns cell into code cell(default)\n",
    "\n",
    "\n",
    "* Ctrl-Enter runs code of cell in place\n",
    "* Alt-Enter runs code for current cell and creates a new cell below\n",
    "* Esc-A creates a new cell above current cell\n",
    "* Esc-B creates a new cell below current cell\n",
    "* Esc-dd deletes current cell"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 22,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Try Esc-B to create a new cell, \n",
    "# Enter print(\"Hello RCS!\")\n",
    "# Press Ctrl-Enter\n",
    "# Did you get any error messages?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Try Esc-B then Esc-M to creata  Markdown cell and write some text"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Text (Markdown) cell\n",
    "\n",
    "[Markdown Basics](https://guides.github.com/features/mastering-markdown/)\n",
    "\n",
    "I want to write a *novel* \n",
    "## 2nd Level Headline\n",
    "\n",
    "* Unordered **List** item 1\n",
    "* List Item 2\n",
    "\n",
    "\n",
    "1. Item 1\n",
    "2. Item 2\n",
    "\n",
    "\n",
    "# Esc - Y makes cell a code cell\n",
    "# Esc - M makes cell a markdown cell"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Variables <a class=\"anchor\" id=\"variables\">\n",
    "    \n",
    "[Back to Table of Contents](#toc)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "metadata": {},
   "outputs": [],
   "source": [
    "miname=\"Voldis\"\n",
    "# Creating our first variable will persist through this workbook once it is run"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Valdis\n",
      "something\n",
      "Voldis Valdis\n"
     ]
    }
   ],
   "source": [
    "print(myname)\n",
    "print(\"something\")\n",
    "print(miname,myname)\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Valdis\n"
     ]
    }
   ],
   "source": [
    "print(myname)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 37,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(str, 'Voldis')"
      ]
     },
     "execution_count": 37,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "myname = \"Voldis\"\n",
    "type(myname), myname"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "metadata": {},
   "outputs": [],
   "source": [
    "y = 2020"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 41,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(333, int)"
      ]
     },
     "execution_count": 41,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "ab1 = 333\n",
    "ab1, type(ab1)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 34,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(42, 42)"
      ]
     },
     "execution_count": 34,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "theAnswer = 42\n",
    "the_answer = 42\n",
    "theAnswer, the_answer"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 40,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(3.14159, float)"
      ]
     },
     "execution_count": 40,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "myPi = 3.14159\n",
    "myPi, type(myPi)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": 36,
   "metadata": {},
   "outputs": [],
   "source": [
    "isHot = True"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 34,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 34,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "isHot"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 39,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "bool"
      ]
     },
     "execution_count": 39,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "type(isHot)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 38,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "int"
      ]
     },
     "execution_count": 38,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# type(variableName) will return variable data type\n",
    "type(theAnswer)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 36,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "str"
      ]
     },
     "execution_count": 36,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "type(myname)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 37,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "bool"
      ]
     },
     "execution_count": 37,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "type(isHot)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# What is the data type of myName ?\n",
    "# How about data type of isHot ?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 38,
   "metadata": {},
   "outputs": [],
   "source": [
    "theAnswer = \"My answer\""
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 39,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "str"
      ]
     },
     "execution_count": 39,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "type(theAnswer)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 42,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "\n",
      "Here is a list of the Python keywords.  Enter any keyword to get more help.\n",
      "\n",
      "False               class               from                or\n",
      "None                continue            global              pass\n",
      "True                def                 if                  raise\n",
      "and                 del                 import              return\n",
      "as                  elif                in                  try\n",
      "assert              else                is                  while\n",
      "async               except              lambda              with\n",
      "await               finally             nonlocal            yield\n",
      "break               for                 not                 \n",
      "\n"
     ]
    }
   ],
   "source": [
    "# Variables cannot be reserved keywords\n",
    "help(\"keywords\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 43,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Someting\n",
      "More stuff\n"
     ]
    }
   ],
   "source": [
    "print(\"Someting\")\n",
    "print(\"More stuff\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 43,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Help on class str in module builtins:\n",
      "\n",
      "class str(object)\n",
      " |  str(object='') -> str\n",
      " |  str(bytes_or_buffer[, encoding[, errors]]) -> str\n",
      " |  \n",
      " |  Create a new string object from the given object. If encoding or\n",
      " |  errors is specified, then the object must expose a data buffer\n",
      " |  that will be decoded using the given encoding and error handler.\n",
      " |  Otherwise, returns the result of object.__str__() (if defined)\n",
      " |  or repr(object).\n",
      " |  encoding defaults to sys.getdefaultencoding().\n",
      " |  errors defaults to 'strict'.\n",
      " |  \n",
      " |  Methods defined here:\n",
      " |  \n",
      " |  __add__(self, value, /)\n",
      " |      Return self+value.\n",
      " |  \n",
      " |  __contains__(self, key, /)\n",
      " |      Return key in self.\n",
      " |  \n",
      " |  __eq__(self, value, /)\n",
      " |      Return self==value.\n",
      " |  \n",
      " |  __format__(self, format_spec, /)\n",
      " |      Return a formatted version of the string as described by format_spec.\n",
      " |  \n",
      " |  __ge__(self, value, /)\n",
      " |      Return self>=value.\n",
      " |  \n",
      " |  __getattribute__(self, name, /)\n",
      " |      Return getattr(self, name).\n",
      " |  \n",
      " |  __getitem__(self, key, /)\n",
      " |      Return self[key].\n",
      " |  \n",
      " |  __getnewargs__(...)\n",
      " |  \n",
      " |  __gt__(self, value, /)\n",
      " |      Return self>value.\n",
      " |  \n",
      " |  __hash__(self, /)\n",
      " |      Return hash(self).\n",
      " |  \n",
      " |  __iter__(self, /)\n",
      " |      Implement iter(self).\n",
      " |  \n",
      " |  __le__(self, value, /)\n",
      " |      Return self<=value.\n",
      " |  \n",
      " |  __len__(self, /)\n",
      " |      Return len(self).\n",
      " |  \n",
      " |  __lt__(self, value, /)\n",
      " |      Return self<value.\n",
      " |  \n",
      " |  __mod__(self, value, /)\n",
      " |      Return self%value.\n",
      " |  \n",
      " |  __mul__(self, value, /)\n",
      " |      Return self*value.\n",
      " |  \n",
      " |  __ne__(self, value, /)\n",
      " |      Return self!=value.\n",
      " |  \n",
      " |  __repr__(self, /)\n",
      " |      Return repr(self).\n",
      " |  \n",
      " |  __rmod__(self, value, /)\n",
      " |      Return value%self.\n",
      " |  \n",
      " |  __rmul__(self, value, /)\n",
      " |      Return value*self.\n",
      " |  \n",
      " |  __sizeof__(self, /)\n",
      " |      Return the size of the string in memory, in bytes.\n",
      " |  \n",
      " |  __str__(self, /)\n",
      " |      Return str(self).\n",
      " |  \n",
      " |  capitalize(self, /)\n",
      " |      Return a capitalized version of the string.\n",
      " |      \n",
      " |      More specifically, make the first character have upper case and the rest lower\n",
      " |      case.\n",
      " |  \n",
      " |  casefold(self, /)\n",
      " |      Return a version of the string suitable for caseless comparisons.\n",
      " |  \n",
      " |  center(self, width, fillchar=' ', /)\n",
      " |      Return a centered string of length width.\n",
      " |      \n",
      " |      Padding is done using the specified fill character (default is a space).\n",
      " |  \n",
      " |  count(...)\n",
      " |      S.count(sub[, start[, end]]) -> int\n",
      " |      \n",
      " |      Return the number of non-overlapping occurrences of substring sub in\n",
      " |      string S[start:end].  Optional arguments start and end are\n",
      " |      interpreted as in slice notation.\n",
      " |  \n",
      " |  encode(self, /, encoding='utf-8', errors='strict')\n",
      " |      Encode the string using the codec registered for encoding.\n",
      " |      \n",
      " |      encoding\n",
      " |        The encoding in which to encode the string.\n",
      " |      errors\n",
      " |        The error handling scheme to use for encoding errors.\n",
      " |        The default is 'strict' meaning that encoding errors raise a\n",
      " |        UnicodeEncodeError.  Other possible values are 'ignore', 'replace' and\n",
      " |        'xmlcharrefreplace' as well as any other name registered with\n",
      " |        codecs.register_error that can handle UnicodeEncodeErrors.\n",
      " |  \n",
      " |  endswith(...)\n",
      " |      S.endswith(suffix[, start[, end]]) -> bool\n",
      " |      \n",
      " |      Return True if S ends with the specified suffix, False otherwise.\n",
      " |      With optional start, test S beginning at that position.\n",
      " |      With optional end, stop comparing S at that position.\n",
      " |      suffix can also be a tuple of strings to try.\n",
      " |  \n",
      " |  expandtabs(self, /, tabsize=8)\n",
      " |      Return a copy where all tab characters are expanded using spaces.\n",
      " |      \n",
      " |      If tabsize is not given, a tab size of 8 characters is assumed.\n",
      " |  \n",
      " |  find(...)\n",
      " |      S.find(sub[, start[, end]]) -> int\n",
      " |      \n",
      " |      Return the lowest index in S where substring sub is found,\n",
      " |      such that sub is contained within S[start:end].  Optional\n",
      " |      arguments start and end are interpreted as in slice notation.\n",
      " |      \n",
      " |      Return -1 on failure.\n",
      " |  \n",
      " |  format(...)\n",
      " |      S.format(*args, **kwargs) -> str\n",
      " |      \n",
      " |      Return a formatted version of S, using substitutions from args and kwargs.\n",
      " |      The substitutions are identified by braces ('{' and '}').\n",
      " |  \n",
      " |  format_map(...)\n",
      " |      S.format_map(mapping) -> str\n",
      " |      \n",
      " |      Return a formatted version of S, using substitutions from mapping.\n",
      " |      The substitutions are identified by braces ('{' and '}').\n",
      " |  \n",
      " |  index(...)\n",
      " |      S.index(sub[, start[, end]]) -> int\n",
      " |      \n",
      " |      Return the lowest index in S where substring sub is found, \n",
      " |      such that sub is contained within S[start:end].  Optional\n",
      " |      arguments start and end are interpreted as in slice notation.\n",
      " |      \n",
      " |      Raises ValueError when the substring is not found.\n",
      " |  \n",
      " |  isalnum(self, /)\n",
      " |      Return True if the string is an alpha-numeric string, False otherwise.\n",
      " |      \n",
      " |      A string is alpha-numeric if all characters in the string are alpha-numeric and\n",
      " |      there is at least one character in the string.\n",
      " |  \n",
      " |  isalpha(self, /)\n",
      " |      Return True if the string is an alphabetic string, False otherwise.\n",
      " |      \n",
      " |      A string is alphabetic if all characters in the string are alphabetic and there\n",
      " |      is at least one character in the string.\n",
      " |  \n",
      " |  isascii(self, /)\n",
      " |      Return True if all characters in the string are ASCII, False otherwise.\n",
      " |      \n",
      " |      ASCII characters have code points in the range U+0000-U+007F.\n",
      " |      Empty string is ASCII too.\n",
      " |  \n",
      " |  isdecimal(self, /)\n",
      " |      Return True if the string is a decimal string, False otherwise.\n",
      " |      \n",
      " |      A string is a decimal string if all characters in the string are decimal and\n",
      " |      there is at least one character in the string.\n",
      " |  \n",
      " |  isdigit(self, /)\n",
      " |      Return True if the string is a digit string, False otherwise.\n",
      " |      \n",
      " |      A string is a digit string if all characters in the string are digits and there\n",
      " |      is at least one character in the string.\n",
      " |  \n",
      " |  isidentifier(self, /)\n",
      " |      Return True if the string is a valid Python identifier, False otherwise.\n",
      " |      \n",
      " |      Use keyword.iskeyword() to test for reserved identifiers such as \"def\" and\n",
      " |      \"class\".\n",
      " |  \n",
      " |  islower(self, /)\n",
      " |      Return True if the string is a lowercase string, False otherwise.\n",
      " |      \n",
      " |      A string is lowercase if all cased characters in the string are lowercase and\n",
      " |      there is at least one cased character in the string.\n",
      " |  \n",
      " |  isnumeric(self, /)\n",
      " |      Return True if the string is a numeric string, False otherwise.\n",
      " |      \n",
      " |      A string is numeric if all characters in the string are numeric and there is at\n",
      " |      least one character in the string.\n",
      " |  \n",
      " |  isprintable(self, /)\n",
      " |      Return True if the string is printable, False otherwise.\n",
      " |      \n",
      " |      A string is printable if all of its characters are considered printable in\n",
      " |      repr() or if it is empty.\n",
      " |  \n",
      " |  isspace(self, /)\n",
      " |      Return True if the string is a whitespace string, False otherwise.\n",
      " |      \n",
      " |      A string is whitespace if all characters in the string are whitespace and there\n",
      " |      is at least one character in the string.\n",
      " |  \n",
      " |  istitle(self, /)\n",
      " |      Return True if the string is a title-cased string, False otherwise.\n",
      " |      \n",
      " |      In a title-cased string, upper- and title-case characters may only\n",
      " |      follow uncased characters and lowercase characters only cased ones.\n",
      " |  \n",
      " |  isupper(self, /)\n",
      " |      Return True if the string is an uppercase string, False otherwise.\n",
      " |      \n",
      " |      A string is uppercase if all cased characters in the string are uppercase and\n",
      " |      there is at least one cased character in the string.\n",
      " |  \n",
      " |  join(self, iterable, /)\n",
      " |      Concatenate any number of strings.\n",
      " |      \n",
      " |      The string whose method is called is inserted in between each given string.\n",
      " |      The result is returned as a new string.\n",
      " |      \n",
      " |      Example: '.'.join(['ab', 'pq', 'rs']) -> 'ab.pq.rs'\n",
      " |  \n",
      " |  ljust(self, width, fillchar=' ', /)\n",
      " |      Return a left-justified string of length width.\n",
      " |      \n",
      " |      Padding is done using the specified fill character (default is a space).\n",
      " |  \n",
      " |  lower(self, /)\n",
      " |      Return a copy of the string converted to lowercase.\n",
      " |  \n",
      " |  lstrip(self, chars=None, /)\n",
      " |      Return a copy of the string with leading whitespace removed.\n",
      " |      \n",
      " |      If chars is given and not None, remove characters in chars instead.\n",
      " |  \n",
      " |  partition(self, sep, /)\n",
      " |      Partition the string into three parts using the given separator.\n",
      " |      \n",
      " |      This will search for the separator in the string.  If the separator is found,\n",
      " |      returns a 3-tuple containing the part before the separator, the separator\n",
      " |      itself, and the part after it.\n",
      " |      \n",
      " |      If the separator is not found, returns a 3-tuple containing the original string\n",
      " |      and two empty strings.\n",
      " |  \n",
      " |  replace(self, old, new, count=-1, /)\n",
      " |      Return a copy with all occurrences of substring old replaced by new.\n",
      " |      \n",
      " |        count\n",
      " |          Maximum number of occurrences to replace.\n",
      " |          -1 (the default value) means replace all occurrences.\n",
      " |      \n",
      " |      If the optional argument count is given, only the first count occurrences are\n",
      " |      replaced.\n",
      " |  \n",
      " |  rfind(...)\n",
      " |      S.rfind(sub[, start[, end]]) -> int\n",
      " |      \n",
      " |      Return the highest index in S where substring sub is found,\n",
      " |      such that sub is contained within S[start:end].  Optional\n",
      " |      arguments start and end are interpreted as in slice notation.\n",
      " |      \n",
      " |      Return -1 on failure.\n",
      " |  \n",
      " |  rindex(...)\n",
      " |      S.rindex(sub[, start[, end]]) -> int\n",
      " |      \n",
      " |      Return the highest index in S where substring sub is found,\n",
      " |      such that sub is contained within S[start:end].  Optional\n",
      " |      arguments start and end are interpreted as in slice notation.\n",
      " |      \n",
      " |      Raises ValueError when the substring is not found.\n",
      " |  \n",
      " |  rjust(self, width, fillchar=' ', /)\n",
      " |      Return a right-justified string of length width.\n",
      " |      \n",
      " |      Padding is done using the specified fill character (default is a space).\n",
      " |  \n",
      " |  rpartition(self, sep, /)\n",
      " |      Partition the string into three parts using the given separator.\n",
      " |      \n",
      " |      This will search for the separator in the string, starting at the end. If\n",
      " |      the separator is found, returns a 3-tuple containing the part before the\n",
      " |      separator, the separator itself, and the part after it.\n",
      " |      \n",
      " |      If the separator is not found, returns a 3-tuple containing two empty strings\n",
      " |      and the original string.\n",
      " |  \n",
      " |  rsplit(self, /, sep=None, maxsplit=-1)\n",
      " |      Return a list of the words in the string, using sep as the delimiter string.\n",
      " |      \n",
      " |        sep\n",
      " |          The delimiter according which to split the string.\n",
      " |          None (the default value) means split according to any whitespace,\n",
      " |          and discard empty strings from the result.\n",
      " |        maxsplit\n",
      " |          Maximum number of splits to do.\n",
      " |          -1 (the default value) means no limit.\n",
      " |      \n",
      " |      Splits are done starting at the end of the string and working to the front.\n",
      " |  \n",
      " |  rstrip(self, chars=None, /)\n",
      " |      Return a copy of the string with trailing whitespace removed.\n",
      " |      \n",
      " |      If chars is given and not None, remove characters in chars instead.\n",
      " |  \n",
      " |  split(self, /, sep=None, maxsplit=-1)\n",
      " |      Return a list of the words in the string, using sep as the delimiter string.\n",
      " |      \n",
      " |      sep\n",
      " |        The delimiter according which to split the string.\n",
      " |        None (the default value) means split according to any whitespace,\n",
      " |        and discard empty strings from the result.\n",
      " |      maxsplit\n",
      " |        Maximum number of splits to do.\n",
      " |        -1 (the default value) means no limit.\n",
      " |  \n",
      " |  splitlines(self, /, keepends=False)\n",
      " |      Return a list of the lines in the string, breaking at line boundaries.\n",
      " |      \n",
      " |      Line breaks are not included in the resulting list unless keepends is given and\n",
      " |      true.\n",
      " |  \n",
      " |  startswith(...)\n",
      " |      S.startswith(prefix[, start[, end]]) -> bool\n",
      " |      \n",
      " |      Return True if S starts with the specified prefix, False otherwise.\n",
      " |      With optional start, test S beginning at that position.\n",
      " |      With optional end, stop comparing S at that position.\n",
      " |      prefix can also be a tuple of strings to try.\n",
      " |  \n",
      " |  strip(self, chars=None, /)\n",
      " |      Return a copy of the string with leading and trailing whitespace remove.\n",
      " |      \n",
      " |      If chars is given and not None, remove characters in chars instead.\n",
      " |  \n",
      " |  swapcase(self, /)\n",
      " |      Convert uppercase characters to lowercase and lowercase characters to uppercase.\n",
      " |  \n",
      " |  title(self, /)\n",
      " |      Return a version of the string where each word is titlecased.\n",
      " |      \n",
      " |      More specifically, words start with uppercased characters and all remaining\n",
      " |      cased characters have lower case.\n",
      " |  \n",
      " |  translate(self, table, /)\n",
      " |      Replace each character in the string using the given translation table.\n",
      " |      \n",
      " |        table\n",
      " |          Translation table, which must be a mapping of Unicode ordinals to\n",
      " |          Unicode ordinals, strings, or None.\n",
      " |      \n",
      " |      The table must implement lookup/indexing via __getitem__, for instance a\n",
      " |      dictionary or list.  If this operation raises LookupError, the character is\n",
      " |      left untouched.  Characters mapped to None are deleted.\n",
      " |  \n",
      " |  upper(self, /)\n",
      " |      Return a copy of the string converted to uppercase.\n",
      " |  \n",
      " |  zfill(self, width, /)\n",
      " |      Pad a numeric string with zeros on the left, to fill a field of the given width.\n",
      " |      \n",
      " |      The string is never truncated.\n",
      " |  \n",
      " |  ----------------------------------------------------------------------\n",
      " |  Static methods defined here:\n",
      " |  \n",
      " |  __new__(*args, **kwargs) from builtins.type\n",
      " |      Create and return a new object.  See help(type) for accurate signature.\n",
      " |  \n",
      " |  maketrans(x, y=None, z=None, /)\n",
      " |      Return a translation table usable for str.translate().\n",
      " |      \n",
      " |      If there is only one argument, it must be a dictionary mapping Unicode\n",
      " |      ordinals (integers) or characters to Unicode ordinals, strings or None.\n",
      " |      Character keys will be then converted to ordinals.\n",
      " |      If there are two arguments, they must be strings of equal length, and\n",
      " |      in the resulting dictionary, each character in x will be mapped to the\n",
      " |      character at the same position in y. If there is a third argument, it\n",
      " |      must be a string, whose characters will be mapped to None in the result.\n",
      "\n"
     ]
    }
   ],
   "source": [
    "help(str)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Reserved Keywords\n",
    "\n",
    "False               class               from                or\n",
    "None                continue            global              pass\n",
    "True                def                 if                  raise\n",
    "and                 del                 import              return\n",
    "as                  elif                in                  try\n",
    "assert              else                is                  while\n",
    "async               except              lambda              with\n",
    "await               finally             nonlocal            yield\n",
    "break               for                 not                 \n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "\n",
    "### Data types in Python 3.x\n",
    "\n",
    "* Integers type(42) int\n",
    "* Floating Point type(3.14) float\n",
    "* Boolean type(True),type(False) bool\n",
    "* String(ordered, immutable char sequence) type(\"OyCaramba\") str\n",
    "* List type([1,2,63,\"aha\",\"youcanmixtypeinsidelist\", [\"even\",\"nest\"]]) list\n",
    "* Dictionary(key:value pairs) type({\"foo\":\"bar\", \"favoriteday\":\"Friday\"}) dict\n",
    "* Tuple - ordered immutable sequence type(\"sup\",7,\"dwarves\") tup\n",
    "* Set (unordered collection of uniques) (\"k\",\"a\",\"r\",\"t\",\"u\",\"p\",\"e\",\"l\",\"i\",\"s\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## More on variables\n",
    "https://realpython.com/python-variables"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Strings\n",
    "* immutable\n",
    "* Unicode support\n",
    "\n",
    "\n",
    "* implement all common sequence operators\n",
    "https://docs.python.org/3/library/stdtypes.html#typesseq-common\n",
    "\n",
    "* string specific methods\n",
    "https://docs.python.org/3/library/stdtypes.html#string-methods"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 44,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Všā\n"
     ]
    }
   ],
   "source": [
    "name = \"Všā\"\n",
    "print(name)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 45,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "3"
      ]
     },
     "execution_count": 45,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# String length\n",
    "len(name)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 46,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "4"
      ]
     },
     "execution_count": 46,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# How is this different from name ?\n",
    "len(\"name\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 47,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'V'"
      ]
     },
     "execution_count": 47,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Getting Individual characters\n",
    "name[0]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'s'"
      ]
     },
     "execution_count": 21,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Getting last char\n",
    "name[-1]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 22,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'i'"
      ]
     },
     "execution_count": 22,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "name[-2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 23,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Valdis'"
      ]
     },
     "execution_count": 23,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "name"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 24,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'d'"
      ]
     },
     "execution_count": 24,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "name[3]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### String Slicing"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Val'"
      ]
     },
     "execution_count": 25,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Slicing syntax\n",
    "# Start at 0 an go until but not including 3\n",
    "name[0:3]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Val'"
      ]
     },
     "execution_count": 26,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "name[:3]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 27,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'al'"
      ]
     },
     "execution_count": 27,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "name[1:3]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 29,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Valdis'"
      ]
     },
     "execution_count": 29,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "name"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Vli'"
      ]
     },
     "execution_count": 28,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "name[0:6:2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 30,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Vli'"
      ]
     },
     "execution_count": 30,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "name[::2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 31,
   "metadata": {},
   "outputs": [],
   "source": [
    "shortName = name[::2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 32,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Vli'"
      ]
     },
     "execution_count": 32,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "shortName"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 33,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'ptte'"
      ]
     },
     "execution_count": 33,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# lets play with food!\n",
    "food = \"potatoes\"\n",
    "food[::2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 34,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'oaos'"
      ]
     },
     "execution_count": 34,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "food[1::2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "food[1:6:2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 35,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'seotatop'"
      ]
     },
     "execution_count": 35,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Pythonic way of reversing a string\n",
    "food[::-1]\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 36,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'poxatoes'"
      ]
     },
     "execution_count": 36,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# modifying strings\n",
    "# unmutability\n",
    "# food[2]=\"x\" is not allowed\n",
    "newfood = food[:2] + \"x\" + food[3:]\n",
    "newfood"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 37,
   "metadata": {},
   "outputs": [],
   "source": [
    "# '', \"\" work the same\n",
    "# '''  For multiline '''\n",
    "longstring = ''' This will be a very long string\n",
    "    and a very long day\n",
    "    and a very long summer\n",
    "'''"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 38,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      " This will be a very long string\n",
      "    and a very long day\n",
      "    and a very long summer\n",
      "\n"
     ]
    }
   ],
   "source": [
    "# print out the longstring\n",
    "print(longstring)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## \"f-strings\", “formatted string literals”\n",
    "\n",
    "In some other languages also known as string interpolation"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 40,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Create myname and favfood variables with appropriate text\n",
    "# Then run the cell below\n",
    "# What would happen if you did not assign variables ?\n",
    "favfood = \"potatoes\""
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 41,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "My name is Valdis and my favorite food is potatoes \n"
     ]
    }
   ],
   "source": [
    "print(f\"My name is {myname} and my favorite food is {favfood} \")\n",
    "# f strings in Python 3.6+ older formatting methods not covered in this course\n",
    "# https://realpython.com/python-f-strings/\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 42,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "My name is Valdis and my favorite food is potatoes\n"
     ]
    }
   ],
   "source": [
    "# Old string concatation method\n",
    "print(\"My name is \" + myname + \" and my favorite food is \" + favfood)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Python Lists\n",
    "\n",
    "* Ordered\n",
    "* Mutable(can change individual members!)\n",
    "* Comma separated between brackets [1,3,2,5,6,2]\n",
    "* Can have duplicates\n",
    "* Can be nested\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 43,
   "metadata": {},
   "outputs": [],
   "source": [
    "newlist = [1,2,3,\"Liftoff!\"]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 44,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[1, 2, 3, 'Liftoff!']"
      ]
     },
     "execution_count": 44,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "newlist"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 45,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[11, 12, 13, 14, 15, 16, 17, 18, 19, 20]\n"
     ]
    }
   ],
   "source": [
    "mylist = list(range(11,21+1,1)) \n",
    "# mylist = [11, 12, 13, 14, 15, 16, 17, 18, 19, 20] would work too but not practical for longer ranges...\n",
    "print(mylist)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Slice notation\n",
    "\n",
    "somestring[start:end:step]\n",
    "\n",
    "somelist[start:end:step]\n",
    "\n",
    "start is at index 0(first element), end is -1 the actual index\n",
    "#### Examples below"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 46,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "11"
      ]
     },
     "execution_count": 46,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist[0]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 47,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[14, 15, 16, 17, 18, 19, 20]"
      ]
     },
     "execution_count": 47,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist[3:]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 49,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[19, 20]"
      ]
     },
     "execution_count": 49,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist[-2:]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 48,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[11, 12, 13, 14, 15, 16, 17, 18]"
      ]
     },
     "execution_count": 48,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist[:-2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 50,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[11, 13, 15, 17, 19]"
      ]
     },
     "execution_count": 50,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist[::2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 51,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'ldi'"
      ]
     },
     "execution_count": 51,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "\"Valdis\"[2:5]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "myname[-1]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "myname[::-1]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 52,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[11, 12, 13, 14, 15, 16, 17, 18, 19, 20]"
      ]
     },
     "execution_count": 52,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "\n",
    "### Common list methods.\n",
    "* list.append(elem) -- adds a single element to the end of the list. Common error: does not return the new list, just modifies the original.\n",
    "* list.insert(index, elem) -- inserts the element at the given index, shifting elements to the right.\n",
    "* list.extend(list2) adds the elements in list2 to the end of the list. Using + or += on a list is similar to using extend().\n",
    "* list.index(elem) -- searches for the given element from the start of the list and returns its index. Throws a ValueError if the element does not appear (use \"in\" to check without a ValueError).\n",
    "* list.remove(elem) -- searches for the first instance of the given element and removes it (throws ValueError if not present)\n",
    "* list.sort() -- sorts the list in place (does not return it). (The sorted() function shown later is preferred.)\n",
    "* list.reverse() -- reverses the list in place (does not return it)\n",
    "* list.pop(index)-- removes and returns the element at the given index. Returns the rightmost element if index is omitted (roughly the opposite of append())."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 53,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 42]"
      ]
     },
     "execution_count": 53,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist.append(42)\n",
    "mylist"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 54,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "42"
      ]
     },
     "execution_count": 54,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist.pop()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 55,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[11, 12, 13, 14, 15, 16, 17, 18, 19, 20]"
      ]
     },
     "execution_count": 55,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 57,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "1"
      ]
     },
     "execution_count": 57,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist.count(14)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 58,
   "metadata": {},
   "outputs": [],
   "source": [
    "mystr = \"this is a string\""
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 59,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'THIS IS A STRING'"
      ]
     },
     "execution_count": 59,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mystr.upper()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 60,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Help on built-in function upper:\n",
      "\n",
      "upper() method of builtins.str instance\n",
      "    Return a copy of the string converted to uppercase.\n",
      "\n"
     ]
    }
   ],
   "source": [
    "help(mystr.upper)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 62,
   "metadata": {},
   "outputs": [],
   "source": [
    "words = mystr.split()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 63,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "['this', 'is', 'a', 'string']"
      ]
     },
     "execution_count": 63,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "words"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 64,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'string'"
      ]
     },
     "execution_count": 64,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "words[-1]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Dictionaries\n",
    "\n",
    "* Collection of Key - Value pairs\n",
    "* also known as associative array\n",
    "* unordered\n",
    "* keys unique in one dictionary\n",
    "* storing, extracting"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 65,
   "metadata": {},
   "outputs": [],
   "source": [
    "mydict = {\"country\":\"Latvia\"} #Key-Value store, also knows as Hashmaps, Keys must be unique"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 66,
   "metadata": {},
   "outputs": [],
   "source": [
    "mydict[\"food\"]=\"potatoes\""
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 67,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'potatoes'"
      ]
     },
     "execution_count": 67,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mydict[\"food\"]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 68,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "'Latvia'"
      ]
     },
     "execution_count": 68,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mydict[\"country\"]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 69,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "2"
      ]
     },
     "execution_count": 69,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "len(mydict)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 70,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{'country': 'Latvia', 'food': 'potatoes'}"
      ]
     },
     "execution_count": 70,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mydict"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": 71,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "dict_keys(['country', 'food'])"
      ]
     },
     "execution_count": 71,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mydict.keys()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 72,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "dict_values(['Latvia', 'potatoes'])"
      ]
     },
     "execution_count": 72,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mydict.values()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "mydict.values()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 73,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 73,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "\"potatoes\" in mydict.values()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 75,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "country Latvia\n",
      "food potatoes\n"
     ]
    }
   ],
   "source": [
    "for key,value in mydict.items():\n",
    "    print(key,value)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 76,
   "metadata": {},
   "outputs": [],
   "source": [
    "mydict['food'] = ['potatoes', 'cheese']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 77,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{'country': 'Latvia', 'food': ['potatoes', 'cheese']}"
      ]
     },
     "execution_count": 77,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mydict"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 79,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{'country': 'Latvia', 'food': ['potatoes', 'cheese', 'milk', 'milk']}"
      ]
     },
     "execution_count": 79,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mydict['food'] = mydict['food'] + ['milk']\n",
    "mydict"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Sets\n",
    "\n",
    "* unordered\n",
    "* uniques only\n",
    "* curly braces {3, 6, 7}"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 80,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{1, 3, 6, 7}\n"
     ]
    }
   ],
   "source": [
    "s={3,3,6,1,3,6,7}\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Tuples\n",
    "\n",
    "*  ordered\n",
    "* immutable (cannot be changed!)\n",
    "* Can be used as a collection of fields"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "mytuple = 6, 4, 9\n",
    "print(mytuple)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Arithmetic Operators <a class=\"anchor\" id=\"arithmetic\">\n",
    "    \n",
    "[Back to Table of Contents](#toc)\n",
    "* `+ - * / `\n",
    "* `**(power)` \n",
    "* `% modulus` \n",
    "* `//(integer division)`\n",
    "* `() parenthesis for order`\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 81,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "14.0"
      ]
     },
     "execution_count": 81,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "5+4*3-(6/2)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 83,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "3"
      ]
     },
     "execution_count": 83,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "7//2\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 84,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "1"
      ]
     },
     "execution_count": 84,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "4%3"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "type(1)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "type(14.0)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "5**33"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 85,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "92709068817830061978520606494193845859707401497097037749844778027824097442147966967457359038488841338006006032592594389655201"
      ]
     },
     "execution_count": 85,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "11**120 # no maximum anymore"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Flow Control <a class=\"anchor\" id=\"flow-control\">\n",
    "    \n",
    "[Back to Table of Contents](#toc)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# With Flow Control we can tell our program/cells to choose different paths"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Conditional operators \n",
    "\n",
    "`< > <= >= == != and or not`"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# What is truth in computer language?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 86,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 86,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "2*2 == 4"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 87,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "False"
      ]
     },
     "execution_count": 87,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "5 > 7\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 89,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "print(5 == int('5'))\n",
    "\n",
    "print(5 <= 6)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 90,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "print(5 <= 5)\n",
    "\n",
    "# check if 5 is NOT equal to 6\n",
    "print(5 != 6)\n",
    "\n",
    "print(5 != 5)\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 91,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 91,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# We check each letter from left side\n",
    "# on mismatch we check ASCII (UTF-8) tables for values\n",
    "\n",
    "'VALDIS' < 'VOLDEMARS'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 92,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 92,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "len('VALDIS') < len('VOLDEMARS')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 93,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 93,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "True and True"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 94,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "False"
      ]
     },
     "execution_count": 94,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "True and False"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 95,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 95,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "True or False"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 98,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 98,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "False or False or False or True"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 99,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "False"
      ]
     },
     "execution_count": 99,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "not True"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 100,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 100,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "not False"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## If Statement"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 102,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Always\n"
     ]
    }
   ],
   "source": [
    "## Conditional execution\n",
    "# if 4 is larger than 5 then do something\n",
    "if 4 > 5:\n",
    "    print(\"4 is larger than 5 wow!\")\n",
    "    print(\"MOre text\")\n",
    "print(\"Always\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 103,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "hello\n",
      "hello\n",
      "hello thats not magic\n"
     ]
    }
   ],
   "source": [
    "if 5 >= 5:\n",
    "    print(\"hello\")\n",
    "if 5 <= 5:\n",
    "    print(\"hello\")\n",
    "if 5 == 6:\n",
    "    print(\"hello thats magic\")\n",
    "if 5 != 6:\n",
    "    print(\"hello thats not magic\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 104,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Do one thing if if is True\n",
      "DO more things if if is True\n",
      "Do this always\n"
     ]
    }
   ],
   "source": [
    "if 2*2 == 4:\n",
    "    print(\"Do one thing if if is True\")\n",
    "    print(\"DO more things if if is True\")\n",
    "print(\"Do this always\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "c = float(input(\"Enter  temperature in Celsius \"))\n",
    "f = c * 9/5 + 32\n",
    "print(\"Farenheit Temperature is\", f)\n",
    "if f > 100:\n",
    "    print(\"You are too hot, find a doctor?\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Try reversing the above program to create a Farenheit to Celsius converter"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 106,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "a is NOT larger than 5\n",
      "Continue as normal\n"
     ]
    }
   ],
   "source": [
    "a = -55\n",
    "if a > 5:\n",
    "    print('a is larger than 5')\n",
    "    # do more stuff\n",
    "else:\n",
    "    print('a is NOT larger than 5')\n",
    "    # do more stuff if a is not larger than 5\n",
    "print(\"Continue as normal\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 108,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Enter an integer please! 42\n",
      "That is the answer to everything!\n",
      "Your number is 42\n"
     ]
    }
   ],
   "source": [
    "#elif comes from else if\n",
    "x = int(input(\"Enter an integer please! \"))\n",
    "if x > 42:\n",
    "    print(\"Too ambitious an answer!\")\n",
    "elif x < 42:\n",
    "    print(\"You dream too little!\")\n",
    "else:\n",
    "    print(\"That is the answer to everything!\")\n",
    "#These lines below will execute always\n",
    "print('Your number is', x)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Loops"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# How would be perform the same/similar action multiple times?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 109,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Alice did \n",
      "talk\n",
      "talk\n",
      "talk\n",
      "talk\n",
      "talk\n"
     ]
    }
   ],
   "source": [
    "i = 0\n",
    "print(\"Alice did \")\n",
    "while i < 5: # notice the colon\n",
    "    print(\"talk\")\n",
    "    i+= 1 # same as i = i + 1"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 110,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "5"
      ]
     },
     "execution_count": 110,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "i"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# What would happen if we did not have i+=1 in our above program ?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 111,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "0\n",
      "1\n",
      "2\n",
      "3\n",
      "4\n",
      "5\n",
      "6\n",
      "7\n",
      "8\n",
      "9\n"
     ]
    }
   ],
   "source": [
    "for x in range(10):\n",
    "    print(x)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 112,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "V\n",
      "a\n",
      "l\n",
      "d\n",
      "i\n",
      "s\n"
     ]
    }
   ],
   "source": [
    "for c in \"Valdis\":\n",
    "    print(c)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 113,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[11, 12, 13, 14, 15, 16, 17, 18, 19, 20]"
      ]
     },
     "execution_count": 113,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "mylist"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 116,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "11\n",
      "12\n",
      "13\n",
      "14\n",
      "15\n",
      "This will happen at the end always\n"
     ]
    }
   ],
   "source": [
    "for item in mylist[:5]:\n",
    "    print(item)\n",
    "    # I could more stuff here\n",
    "print('This will happen at the end always')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 117,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "country Latvia\n",
      "food ['potatoes', 'cheese', 'milk', 'milk']\n"
     ]
    }
   ],
   "source": [
    "for k,v in mydict.items():\n",
    "    print(k,v)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 118,
   "metadata": {},
   "outputs": [],
   "source": [
    "## Splitting a line of text into words\n",
    "mytext = \"A quick brown fox jumped over a sleeping dog\"\n",
    "words = mytext.split()\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 119,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "['A', 'quick', 'brown', 'fox', 'jumped', 'over', 'a', 'sleeping', 'dog']\n"
     ]
    }
   ],
   "source": [
    "print(words)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 120,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "A True True\n",
      "q False False\n",
      "b False False\n",
      "f False False\n",
      "j False False\n",
      "o False False\n",
      "a False False\n",
      "s False False\n",
      "d False False\n"
     ]
    }
   ],
   "source": [
    "## Print first letter of each word\n",
    "for w in words:\n",
    "    print(w[0], w[0].isupper(), w.istitle()) ## istitle() checks every word in a string so not good for unsplit strings"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 121,
   "metadata": {},
   "outputs": [],
   "source": [
    "myline=\"Mr. Sherlock Holmes, who was usually very late in the mornings\""
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "words=myline.split()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "words"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "words[1][0].isupper()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Enumerate for showing index of item when going through many items\n",
    "for i, x in enumerate(range(10,15)):\n",
    "    print(i, x)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 122,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "0 V\n",
      "1 a\n",
      "2 l\n",
      "3 d\n",
      "4 i\n",
      "5 s\n"
     ]
    }
   ],
   "source": [
    "for i, c in enumerate(myname):\n",
    "    print(i, c)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## What is a function? <a class=\"anchor\" id=\"functions\">\n",
    "    \n",
    "[Back to Table of Contents](#toc)\n",
    "* A function is a block of organized, reusable code that is used to perform a single, related action.\n",
    "* Single, organized, related always ? :)\n",
    "###  DRY - Do not Repeat Yourself principle\n",
    "* Every piece of knowledge must have a single, unambiguous, authoritative representation within a system. http://wiki.c2.com/?DontRepeatYourself\n",
    "\n",
    "* Contrast WET - We Enjoy Typing, Write Everything Twice, Waste Everyone's Time"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 123,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Here we define our first function\n",
    "def myFirstFunc():\n",
    "    print(\"Running My first func\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 125,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Running My first func\n"
     ]
    }
   ],
   "source": [
    "# function has to be defined before it is called\n",
    "myFirstFunc()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 126,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Passing parameters(arguments)\n",
    "def printName(name):\n",
    "    print(f\"Maybe my name is: {name}\")\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 127,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Maybe my name is: Valdis\n"
     ]
    }
   ],
   "source": [
    "printName(\"Valdis\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 128,
   "metadata": {},
   "outputs": [],
   "source": [
    "def add(a, b):\n",
    "    print(a+b)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 129,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "10\n",
      "242\n",
      "Hello Riga\n",
      "[1, 2, 7, 6, 7, 8, 9, 10, 11]\n"
     ]
    }
   ],
   "source": [
    "add(4,6)\n",
    "add(9,233)\n",
    "add(\"Hello \",\"Riga\")\n",
    "add([1,2,7],list(range(6,12)))\n",
    "# Try calling add function with other parameters"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 130,
   "metadata": {},
   "outputs": [],
   "source": [
    "# We make Docstrings with '''Helpful function description inside'''\n",
    "def mult(a, b):\n",
    "    '''Returns \n",
    "    multiple from first two arguments'''\n",
    "    print(\"Look ma I am multiplying!\", a, b, a*b)\n",
    "    return a*b"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 131,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Look ma I am multiplying! 4 5 20\n"
     ]
    },
    {
     "data": {
      "text/plain": [
       "20"
      ]
     },
     "execution_count": 131,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "res = mult(4,5)\n",
    "res"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "def printnum(num):\n",
    "    if num > 10:\n",
    "        print(f\"This number {num} is too unwieldy for me to print\")\n",
    "    else:\n",
    "        print(f\"This {num} is a nice number\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "def isEven(num):\n",
    "    if num%2 == 0:\n",
    "        print(f\"{num} is even\")\n",
    "    else:\n",
    "        print(f\"{num} is odd\")\n",
    "\n",
    "isEven(3)\n",
    "isEven(4)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "def processLine(line):\n",
    "    words = line.split()\n",
    "    linegood=False\n",
    "    for word in words:        \n",
    "        if word[0].isupper():\n",
    "            print(word, end='\\t')\n",
    "            linegood=True\n",
    "    if linegood == True:\n",
    "        print('')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Libraries <a class=\"anchor\" id=\"libraries\">\n",
    "    \n",
    "[Back to Table of Contents](#toc)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Python and Batteries Included Philosophy\n",
    "## Why reinvent the wheel?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 132,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The Zen of Python, by Tim Peters\n",
      "\n",
      "Beautiful is better than ugly.\n",
      "Explicit is better than implicit.\n",
      "Simple is better than complex.\n",
      "Complex is better than complicated.\n",
      "Flat is better than nested.\n",
      "Sparse is better than dense.\n",
      "Readability counts.\n",
      "Special cases aren't special enough to break the rules.\n",
      "Although practicality beats purity.\n",
      "Errors should never pass silently.\n",
      "Unless explicitly silenced.\n",
      "In the face of ambiguity, refuse the temptation to guess.\n",
      "There should be one-- and preferably only one --obvious way to do it.\n",
      "Although that way may not be obvious at first unless you're Dutch.\n",
      "Now is better than never.\n",
      "Although never is often better than *right* now.\n",
      "If the implementation is hard to explain, it's a bad idea.\n",
      "If the implementation is easy to explain, it may be a good idea.\n",
      "Namespaces are one honking great idea -- let's do more of those!\n"
     ]
    }
   ],
   "source": [
    "# Try importing this\n",
    "import this"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 133,
   "metadata": {},
   "outputs": [],
   "source": [
    "import math\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 134,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "-0.9999987317275395"
      ]
     },
     "execution_count": 134,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# notice the . syntax helper\n",
    "math.cos(3.14)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "math."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 139,
   "metadata": {},
   "outputs": [],
   "source": [
    "from collections import Counter"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 140,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "Counter({'a': 5, 'b': 2, 'r': 2, 'c': 1, 'd': 1})"
      ]
     },
     "execution_count": 140,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "magic = \"abracadabra\"\n",
    "cnt = Counter(magic)\n",
    "cnt"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# There are hundreds of useful Python libraries\n",
    "## Crucial libraries are collected in Standard Library\n",
    "# https://docs.python.org/3/library/\n",
    "# Batteries included\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 137,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "['__add__',\n",
       " '__and__',\n",
       " '__class__',\n",
       " '__contains__',\n",
       " '__delattr__',\n",
       " '__delitem__',\n",
       " '__dict__',\n",
       " '__dir__',\n",
       " '__doc__',\n",
       " '__eq__',\n",
       " '__format__',\n",
       " '__ge__',\n",
       " '__getattribute__',\n",
       " '__getitem__',\n",
       " '__gt__',\n",
       " '__hash__',\n",
       " '__iadd__',\n",
       " '__iand__',\n",
       " '__init__',\n",
       " '__init_subclass__',\n",
       " '__ior__',\n",
       " '__isub__',\n",
       " '__iter__',\n",
       " '__le__',\n",
       " '__len__',\n",
       " '__lt__',\n",
       " '__missing__',\n",
       " '__module__',\n",
       " '__ne__',\n",
       " '__neg__',\n",
       " '__new__',\n",
       " '__or__',\n",
       " '__pos__',\n",
       " '__reduce__',\n",
       " '__reduce_ex__',\n",
       " '__repr__',\n",
       " '__setattr__',\n",
       " '__setitem__',\n",
       " '__sizeof__',\n",
       " '__str__',\n",
       " '__sub__',\n",
       " '__subclasshook__',\n",
       " '__weakref__',\n",
       " '_keep_positive',\n",
       " 'clear',\n",
       " 'copy',\n",
       " 'elements',\n",
       " 'fromkeys',\n",
       " 'get',\n",
       " 'items',\n",
       " 'keys',\n",
       " 'most_common',\n",
       " 'pop',\n",
       " 'popitem',\n",
       " 'setdefault',\n",
       " 'subtract',\n",
       " 'update',\n",
       " 'values']"
      ]
     },
     "execution_count": 137,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "dir(cnt)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 138,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[('a', 5), ('b', 2), ('r', 2), ('c', 1), ('d', 1)]"
      ]
     },
     "execution_count": 138,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "cnt.most_common()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Most important Python ideas <a class=\"anchor\" id=\"python-ideas\">\n",
    "    \n",
    "[Back to Table of Contents](#toc)\n",
    "\n",
    "* dir(myobject) to find what can be done (most decent text editors/IDEs will offer autocompletion and hints though)\n",
    "* help(myobject) general help\n",
    "* type(myobject) what type it is\n",
    "\n",
    "## Slicing Syntax for sequences(strings,lists and more)\n",
    "`\n",
    "myname[start:end:step]\n",
    "myname[:5]`\n",
    "\n",
    "## : indicates a new indentation level \n",
    "\n",
    "`if x > 5:\n",
    "     print(\"Do Work when x > 5\")\n",
    "print(\"Always Do this\")`"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Python Resources <a class=\"anchor\" id=\"learning-resources\">\n",
    "    \n",
    "[Back to Table of Contents](#toc)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Wiki for Tutorials\n",
    "\n",
    "https://wiki.python.org/moin/BeginnersGuide/NonProgrammers"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Tutorials Begginner to Intermediate\n",
    "\n",
    "\n",
    "\n",
    "\n",
    "* https://automatetheboringstuff.com/ - Anything by Al Sweigart is great\n",
    "* http://newcoder.io/tutorials/ - 5 sets of practical tutorials\n",
    "* [Think Like a Computer Scientist](http://interactivepython.org/runestone/static/thinkcspy/index.html) full tutorial\n",
    "* [Non-Programmers Tutorial for Python 3](https://en.wikibooks.org/wiki/Non-Programmer%27s_Tutorial_for_Python_3) quite good for wikibooks\n",
    "* [Real Python](https://realpython.com/) Python Tutorials for all levels\n",
    "\n",
    "\n",
    "* [Learn Python 3 the Hard Way](https://learnpythonthehardway.org/python3/intro.html) controversial author but very exhaustive, some like this approach"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## More Advanced Python Specific Books\n",
    "\n",
    "* [Python Cookbook](https://www.amazon.com/Python-Cookbook-Third-David-Beazley/dp/1449340377) Recipes for specific situations\n",
    "\n",
    "* [Effective Python](https://effectivepython.com/) best practices\n",
    "* [Fluent Python](http://shop.oreilly.com/product/0636920032519.do) **highly recommended**, shows Python's advantages"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## General Best Practices Books\n",
    "#### (not Python specific)\n",
    "\n",
    "* [Code Complete 2](https://www.goodreads.com/book/show/4845.Code_Complete) - Fantastic best practices\n",
    "* [The Mythical Man-Month](https://en.wikipedia.org/wiki/The_Mythical_Man-Month) - No silver bullet even after 40 years.\n",
    "* [The Pragmatic Programmer](https://www.amazon.com/Pragmatic-Programmer-Journeyman-Master/dp/020161622X) - More practical advice\n",
    "* [Clean Code](https://www.amazon.com/Clean-Code-Handbook-Software-Craftsmanship/dp/0132350882) - more towards agile"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Blogs / Personalities / forums\n",
    "\n",
    "* [Dan Bader](https://dbader.org/)\n",
    "* [Reddit Python](https://www.reddit.com/r/python)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Exercises/Challenges\n",
    "* http://www.pythonchallenge.com/ - first one is easy but after that...\n",
    "* [Advent of Code](https://adventofcode.com/) - yearly programming challenges\n",
    "* https://projecteuler.net/ - gets very mathematical but first problems are great for testing "
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Explore Public Notebooks on Github\n",
    " Download them and try them out for yourself\n",
    " \n",
    "https://github.com/jupyter/jupyter/wiki/A-gallery-of-interesting-Jupyter-Notebooks"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Questions / Suggestions ? \n",
    "\n",
    "Pull requests welcome\n",
    "\n",
    "e-mail **valdis.s.coding at gmail.com**"
   ]
  }
 ],
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