03 - Primitive types.ipynb

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    "# Primitive types\n",
    "\n",
    "Python has several different primary **data types** (types), which serve as the primary building blocks of the language. These are the most simple units, but can be combined in nearly infinite ways to produce code. \n",
    "\n",
    "Of the different primary data types, we identify the four major ones: \n",
    "1. Integers\n",
    "2. Floats\n",
    "3. Strings\n",
    "4. Booleans\n",
    "\n",
    "We present and review the basic **operations** and **comparisons** of each of these data types. "
   ]
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   "source": [
    "## 1. Numbers (integers and floats)"
   ]
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       "int"
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   "source": [
    "type(1)"
   ]
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       "float"
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   "source": [
    "type(2.5)"
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   "source": [
    "### 1.1. Operations"
   ]
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     "text": [
      "2\n"
     ]
    }
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   "source": [
    "#addition\n",
    "print(1+1)"
   ]
  },
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   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "-2\n"
     ]
    }
   ],
   "source": [
    "#subtraction\n",
    "print(8-10)"
   ]
  },
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     "text": [
      "20\n",
      "13.5\n"
     ]
    }
   ],
   "source": [
    "#multiplication\n",
    "print(4*5)\n",
    "print(3*4.5)"
   ]
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   "outputs": [
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     "text": [
      "8.5\n",
      "5.0\n"
     ]
    }
   ],
   "source": [
    "#division\n",
    "#since Python 3, divisions (regardless of the input types) will always produce floats)\n",
    "print(17/2)\n",
    "print(10/2)"
   ]
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     "text": [
      "16\n",
      "5.0\n"
     ]
    }
   ],
   "source": [
    "#power\n",
    "print(2**4)\n",
    "print(25**0.5)"
   ]
  },
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   "execution_count": 8,
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     "text": [
      "0\n",
      "1\n"
     ]
    }
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   "source": [
    "#the modulo is the remainer of the whole division\n",
    "print(81%9)\n",
    "print(17%2)"
   ]
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   "source": [
    "### 1.2. Built-in function\n",
    "Python ships with a few built-in functions, which you can use in any context. "
   ]
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     "text": [
      "1\n"
     ]
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   "source": [
    "#cast (i.e. convert) a float to an integer\n",
    "#if the input of the function is a float, it will truncate the number to the lower integer\n",
    "print(int(1.6))"
   ]
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     "text": [
      "4.4\n"
     ]
    }
   ],
   "source": [
    "#and cast an integer to a float\n",
    "print(float(4.4))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
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   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "4\n"
     ]
    }
   ],
   "source": [
    "#absolute value\n",
    "print(abs(-4))"
   ]
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   "cell_type": "code",
   "execution_count": 12,
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   "outputs": [
    {
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     "text": [
      "8\n",
      "9\n"
     ]
    }
   ],
   "source": [
    "print(round(17/2))\n",
    "print(round(17.9/2))"
   ]
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   "source": [
    "### 1.3. Comparisons\n",
    "You can compare number to each other using the below comparators. Each comparison, if successful, will return either `True` or a `False` (what we will later see is `boolean`). You can compare float numbers and integers with no distinction.  "
   ]
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     "text": [
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#is equal to\n",
    "#read the below: is 8 equal to 8\n",
    "#notice the use of 2 equal signs\n",
    "print(8 == 8)\n",
    "print(2 == 3)"
   ]
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     "text": [
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#is not equal to \n",
    "print(10 != 9)\n",
    "print(14 != (15 - 1))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
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   "outputs": [
    {
     "name": "stdout",
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     "text": [
      "True\n"
     ]
    }
   ],
   "source": [
    "#you can use floats and integers interchangeable\n",
    "print(2 == 2.0)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
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    {
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     "text": [
      "False\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "#is greater (or equal to)\n",
    "print(3 > 3.0)\n",
    "print(3 >= 3)"
   ]
  },
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   "execution_count": 17,
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    {
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     "text": [
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#is less than (or equal to)\n",
    "print(14 < 20)\n",
    "print(10 <= 9)"
   ]
  },
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   "source": [
    "### 1.3. Caveats, tips and tricks"
   ]
  },
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     "output_type": "stream",
     "text": [
      "3.3000000000000003\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "#Beward... what may appear exact isn't.\n",
    "#There are work-arounds to this, but for now, understand that floats have precision to 15 decimal places.\n",
    "print(1.1 + 2.2)\n",
    "print((1.1 + 2.2) != 3.3)"
   ]
  },
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   "cell_type": "code",
   "execution_count": 19,
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    {
     "ename": "ZeroDivisionError",
     "evalue": "division by zero",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mZeroDivisionError\u001b[0m                         Traceback (most recent call last)",
      "\u001b[0;32m<ipython-input-19-01eeaa28f94c>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0;31m#errors you'll likely encounter\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 2\u001b[0;31m \u001b[0;36m1\u001b[0m\u001b[0;34m/\u001b[0m\u001b[0;36m0\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mZeroDivisionError\u001b[0m: division by zero"
     ]
    }
   ],
   "source": [
    "#errors you'll likely encounter\n",
    "1/0"
   ]
  },
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   "source": [
    "## 2. Strings"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
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    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello, there\n",
      "You are learning Python!\n"
     ]
    }
   ],
   "source": [
    "#Strings are sequences of characters delimited by single or double quotation marks\n",
    "print(\"Hello, there\")\n",
    "print('You are learning Python!')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
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    "collapsed": false,
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   "outputs": [
    {
     "data": {
      "text/plain": [
       "str"
      ]
     },
     "execution_count": 21,
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     "output_type": "execute_result"
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   ],
   "source": [
    "type('The type (also known as its class) of a string is a string')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 22,
   "metadata": {
    "collapsed": false,
    "deletable": true,
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   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "You're doing great, keep it up!\n"
     ]
    }
   ],
   "source": [
    "#When you need to use quotation marks within a string, you must escape it with a backslash\n",
    "print('You\\'re doing great, keep it up!')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 23,
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     "text": [
      "\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",
      "\n"
     ]
    }
   ],
   "source": [
    "#Very long strings, with return cariages can be delimited with triple strings\n",
    "print(\"\"\"\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",
    "\"\"\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "### 2.1. Operations\n",
    "There aren't that many operations you can do on strings..."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 24,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Hello there, my name is Tom\n"
     ]
    }
   ],
   "source": [
    "#concatenate two strings together\n",
    "print(\"Hello there, my name is \" + \"Tom\")"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "### 2.2. Built-in function"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "metadata": {
    "collapsed": false,
    "deletable": true,
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   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "This is already a string\n",
      "1\n",
      "4.5\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "#convert another data type to a string\n",
    "print(str('This is already a string'))\n",
    "print(str(1))\n",
    "print(str(4.5))\n",
    "print(str(True))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "25\n"
     ]
    }
   ],
   "source": [
    "#compute the length of a string\n",
    "print(len('anticonstitutionnellement'))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "What is your name? David\n",
      "David\n"
     ]
    }
   ],
   "source": [
    "#request user input\n",
    "print(input('What is your name? '))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 29,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "How old are you? 27\n",
      "27\n"
     ]
    }
   ],
   "source": [
    "#Understand that the input function returns a string, even if it looks like a number\n",
    "print(input(\"How old are you? \"))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "### 2.3. Comparisons"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 30,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#you can compare two strings to each other\n",
    "print('David' == 'David')\n",
    "print('Céline' == 'David')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 31,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "False\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#comparison is case and accent sensitive\n",
    "print('David' == 'DAVID')\n",
    "print('Céline' == 'Celine')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 32,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "False\n"
     ]
    }
   ],
   "source": [
    "#and comparisons of a string with a number is always false\n",
    "print(\"1\" == 1)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
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   "source": [
    "### 2.4. String methods\n",
    "\n",
    "Note this: everything in Python is an object, in other words, are instances of a given class. The number 1 for example is an instance of an integer, while 3.3 is an instance of a float. And in Python, most objects have **methods** - functions that you can call on an instance to change or create a new modified instance.\n",
    "\n",
    "Methods are called on an instance by using the **.** operator. The below may make more sense. "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 33,
   "metadata": {
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    "deletable": true,
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   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "IMF\n"
     ]
    }
   ],
   "source": [
    "#convert a string to its uppercase representation\n",
    "print(\"imf\".upper())"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 34,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "www\n"
     ]
    }
   ],
   "source": [
    "#or to its lowercase representation\n",
    "print(\"WWW\".lower())"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 35,
   "metadata": {
    "collapsed": false,
    "deletable": true,
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   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "I often forget to capitalize the first letter of a sentence\n"
     ]
    }
   ],
   "source": [
    "#capitalize the first letter of a string\n",
    "print(\"i often forget to capitalize the first letter of a sentence\".capitalize())"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 36,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "George W. Bush\n"
     ]
    }
   ],
   "source": [
    "#title case\n",
    "print(\"george w. bush\".title())"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 37,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#ends with and starts with\n",
    "print(\"www.google.co.uk\".endswith(\"co.uk\"))\n",
    "print(\"+447123456789\".startswith(\"+33\"))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 38,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "please delete this obnoxious preceeding space\n",
      "and this traing space too\n",
      "they are so annoying\n"
     ]
    }
   ],
   "source": [
    "#remove preceeding, trailing or both white space\n",
    "print('  please delete this obnoxious preceeding space'.lstrip())\n",
    "print('and this traing space too  '.rstrip())\n",
    "print('   they are so annoying    '.strip())"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 39,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "I really like to code\n"
     ]
    }
   ],
   "source": [
    "#replace text\n",
    "print(\"I really like to cook\".replace(\"cook\", \"code\"))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 40,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "False\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#is text numeric: composed of purely numbers\n",
    "print(\"123\".isnumeric())\n",
    "print(\"I am 29 years old\".isnumeric())\n",
    "\n",
    "#note this! \n",
    "print(\"34.8\".isnumeric())"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 41,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n"
     ]
    }
   ],
   "source": [
    "#as many space bar hits as you want\n",
    "print(\"       \".isspace())"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 42,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#is made of letters only\n",
    "print(\"ABCDEFGHIJKLMNOPQRSTUVWXYZ\".isalpha())\n",
    "\n",
    "#space is not a letter\n",
    "print(\"ABCDEFGHIJKLMNOPQRSTUVWXYZ \".isalpha())"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 43,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "I live in London\n",
      "... and since yesterday, I am 27 years old\n"
     ]
    }
   ],
   "source": [
    "#inject values in placeholders\n",
    "print(\"I live in {}\".format(\"London\"))\n",
    "print(\"... and since {}, I am {} years old\".format(\"yesterday\", 27))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 44,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "14\n",
      "-1\n"
     ]
    }
   ],
   "source": [
    "#find the position of the first occurence of a string in another\n",
    "#this returns -1 when it cannot find the string\n",
    "print('I am learning Python'.find('Py'))\n",
    "print('I like apples'.find('pears'))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 45,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "14\n"
     ]
    }
   ],
   "source": [
    "#alternatively, use the .index() method\n",
    "print('I am learning Python'.index('Python'))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 46,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "ename": "ValueError",
     "evalue": "substring not found",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mValueError\u001b[0m                                Traceback (most recent call last)",
      "\u001b[0;32m<ipython-input-46-e334f1ab04f4>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0;31m#but unlike the .find() method, the .index() method will raise an errors if not found\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 2\u001b[0;31m \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m'I am unlearning Excel'\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mindex\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m'Python'\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mValueError\u001b[0m: substring not found"
     ]
    }
   ],
   "source": [
    "#but unlike the .find() method, the .index() method will raise an errors if not found\n",
    "print('I am unlearning Excel'.index('Python'))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "## 3. Booleans\n",
    "There are only two possible boolean values: `True` and `False`"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 47,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "print(True)\n",
    "print(False)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 48,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "bool"
      ]
     },
     "execution_count": 48,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "type(True)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 49,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n"
     ]
    }
   ],
   "source": [
    "#These are normally created as the result of an operation\n",
    "print(25 > 8)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "### 3.1. Operations"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 50,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "True\n",
      "False\n",
      "False\n",
      "False\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#AND operator\n",
    "print(True and True)\n",
    "print((2 > 1) and (14 >= 14))\n",
    "\n",
    "print(True and False)\n",
    "print((2 > 0) and (15 < 5))\n",
    "\n",
    "print(False and False)\n",
    "print((\"King\" == \"Queen\") and (\"France\" == \"UK\"))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 51,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true,
    "scrolled": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#OR operator\n",
    "print(True or False)\n",
    "print(True or True)\n",
    "print(False or False)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 52,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "False\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "#inverse\n",
    "print(not True)\n",
    "print(not False)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 53,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "False\n",
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#the XOR operator (exclusive or)\n",
    "#return True if only one of two options is True, not both\n",
    "print(True ^ True)\n",
    "print(True ^ False)\n",
    "print(False ^ False)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "### 3.2. Built-in function"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 54,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#cast a value to a boolean\n",
    "print(bool(True))\n",
    "print(bool(1))\n",
    "print(bool(0))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 55,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Any string is always True\n",
      "Except for the empty string, which is False\n",
      "Any number is equal to True\n",
      "Except for 0, which is equal to False\n"
     ]
    }
   ],
   "source": [
    "#note the following - perhaps surprising to the beginner - results\n",
    "print('Any string is always', bool('abc'))\n",
    "print('Except for the empty string, which is', bool(''))\n",
    "print('Any number is equal to', bool(-1.5))\n",
    "print('Except for 0, which is equal to', bool(0))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "### 3.3. Comparisons"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 56,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "True\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "#is equal to \n",
    "print(True == True)\n",
    "print(False != True)\n",
    "print(False == False)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 57,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#note the following\n",
    "print(1 == True)\n",
    "print(0 == True)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 58,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "False\n",
      "True\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "#no string will ever compare to True, even if it is cast to a True\n",
    "print('Is this True?' == True)\n",
    "print(bool('But we said strings are cast to True'))\n",
    "print(bool('Ahhhh! So everything must be explicit') == True)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 59,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "#You can also use the keyword 'is'\n",
    "print((2 * 4 == 8) is True)\n",
    "print((3 > 4) is not True)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 60,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "True\n",
      "False\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "#the 'is' operator is stricter than ==\n",
    "print(1 == True)\n",
    "print(0 == False)\n",
    "\n",
    "print(1 is True)\n",
    "print(0 is False)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "## 4. None\n",
    "None is a special data type, and represents the absence of value. "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 61,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "None\n"
     ]
    }
   ],
   "source": [
    "print(None)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 62,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "NoneType"
      ]
     },
     "execution_count": 62,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "type(None)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "### 4.1. Operations"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 63,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n"
     ]
    }
   ],
   "source": [
    "#not None casts to True...\n",
    "print(not None)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "### 4.2. Comparisons"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 64,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "print(None == None)\n",
    "print(None is None)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 65,
   "metadata": {
    "collapsed": false,
    "deletable": true,
    "editable": true
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "True\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "#note that None is neither True nor False\n",
    "print(None != True)\n",
    "print(None != False)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "## 5. More\n",
    "There are other data types, but these are the essential primary datatypes. Other data types includes `bytes` and the `complex` data type (to represent complex numbers), but most users will only need to handle the above primary data types. As we noted above, instances of each data type are objects. We will return later to this concept of objects. More importantly for now, it is important to note that each of these data types are **immutable**: 1 will always have the value of 1, regardless of what happens; likewise, the letter \"A\" will always be just that: the letter \"A\". We will return to this notion of immutability later in the course.  "
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "## 6. Your turn to play! "
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "### Problem 1\n",
    "Name the 5 data types that we have seen"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true,
    "deletable": true,
    "editable": true
   },
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {
    "deletable": true,
    "editable": true
   },
   "source": [
    "### Problem 2\n",
    "Concatenate and print your first name and your last name"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true,
    "deletable": true,
    "editable": true
   },
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Problem 3\n",
    "A car travels 120km in 2 hours. Print to the console the speed at which the car travelled the distance."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Problem 4\n",
    "The same car travels at 75km/h for another 45 minutes. Print to the console the average speed during the entire trip."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": []
  }
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