12-variable-scope.ipynb

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    "# Variable Scope"
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    "## The scope of a variable is the part of a program that can 'see' that variable.\n",
    "\n",
    "- There are only so many sensible names for variables.\n",
    "- People using functions shouldn’t have to worry about what variable names the author of the function used.\n",
    "- People writing functions shouldn’t have to worry about what variable names the function’s caller uses.\n",
    "- The part of a program in which a variable is visible is called its _scope_."
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    "pressure = 103.9\n",
    "\n",
    "def adjust(t):\n",
    "    temperature = t * 1.43 / pressure\n",
    "    return temperature"
   ]
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    "- `pressure` is a _global variable_.\n",
    "  - Defined outside any particular function.\n",
    "  - Visible everywhere.\n",
    "- `t` and `temperature` are _local variables_ in `adjust`.\n",
    "  - Defined in the function\n",
    "  - Not visible in the main program.\n",
    "  - Remember: a function parameter is a variable that is automatically assigned a value when the function is called."
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    "print('adjusted:', adjust(0.9))\n",
    "print('temperature after call:', temperature)"
   ]
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