lab-b.ipynb

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    "# Cultural and Literary Text Mining\n",
    "## Lab Session B: Python Fundamentals [1]\n",
    "\n",
    "**Date**: June 28\n",
    "\n",
    "**Author**: Kent K. Chang\n",
    "\n",
    "**Accompanying slides**: [link](http://caltmig.kentchang.com/lab/slides/python-fundamentals-1.html#/)\n",
    "\n",
    "* * *\n",
    "\n",
    "## Returning to Basics\n",
    "\n",
    "### The assignment operator and memory location"
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    "pi = 3\n",
    "radius = 11\n",
    "area = pi * (radius**2)\n",
    "radius = 14\n",
    "\n",
    "print('The memory address of the variable pi is ' + str(id(pi)) + \n",
    "      ' which holds the value of ' + str(pi) + '.')\n",
    "print('The memory address of the variable radius is ' + str(id(radius)))\n",
    "print('The memory address of the variable area is ' + str(id(area)))"
   ]
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    "The fact that strings are non-scalars and can be looped through:"
   ]
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    "test_str = 'Crew3'\n",
    "\n",
    "for char in test_str:\n",
    "    print('The memory address of ' + char + ' is: ' + str(id(char)) + '.')"
   ]
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    "## The implications of mutability: motivation\n",
    "\n",
    "Confession time: I made a mistake in Notebook 1.\n",
    "\n",
    "The following is based on Guttag 68-75. I want to show why I think this code from Notebook 1 is bad\n",
    "\n",
    "```python\n",
    "happy_prince_tales = ['\\\"' + happy_prince_tale + '\\\"' for happy_prince_tale in happy_prince_tales]\n",
    "```\n",
    "\n",
    "### Value vs. object equality\n",
    "\n",
    "First, run:"
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    "Techs = ['MIT', 'Caltech']\n",
    "Ivys = ['Harvard', 'Yale', 'Brown']\n",
    "Univs = [Techs, Ivys]\n",
    "Univs1 = [['MIT', 'Caltech'], ['Harvard', 'Yale', 'Brown']]"
   ]
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   "source": [
    "**Homework:** With those variables and lists ready, run: \n",
    "```python\n",
    "print(Univs == Univs1)\n",
    "print(id(Univs) == id(Univs1))\n",
    "```\n",
    "What are the outputs? Try to explain them."
   ]
  }
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