{
"cells": [
{
"cell_type": "markdown",
"metadata": {},
"source": [
"...on parlait de **[programmation impérative](https://fr.wikipedia.org/wiki/Programmation_imp%C3%A9rative) [structurée](https://fr.wikipedia.org/wiki/Programmation_structur%C3%A9e)**..."
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"# Les instructions de base"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Instructions d'assignation"
]
},
{
"cell_type": "code",
"execution_count": 1,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"5\n"
]
}
],
"source": [
"a = 3\n",
"b = 2\n",
"print(a+b)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"### Pour connaître les variables qui sont définies dans le _scope_ actuel :"
]
},
{
"cell_type": "code",
"execution_count": 2,
"metadata": {},
"outputs": [
{
"data": {
"text/plain": [
"['In',\n",
" 'Out',\n",
" '_',\n",
" '__',\n",
" '___',\n",
" '__builtin__',\n",
" '__builtins__',\n",
" '__doc__',\n",
" '__loader__',\n",
" '__name__',\n",
" '__package__',\n",
" '__spec__',\n",
" '_dh',\n",
" '_i',\n",
" '_i1',\n",
" '_i2',\n",
" '_ih',\n",
" '_ii',\n",
" '_iii',\n",
" '_oh',\n",
" 'a',\n",
" 'b',\n",
" 'exit',\n",
" 'get_ipython',\n",
" 'quit']"
]
},
"execution_count": 2,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"dir()"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"### Pour effacer une variable :"
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {},
"outputs": [],
"source": [
"z = 2\n",
"del(z)"
]
},
{
"cell_type": "code",
"execution_count": 4,
"metadata": {},
"outputs": [
{
"ename": "NameError",
"evalue": "name 'z' is not defined",
"output_type": "error",
"traceback": [
"\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
"\u001b[0;31mNameError\u001b[0m Traceback (most recent call last)",
"\u001b[0;32m<ipython-input-4-3a710d2a84f8>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mz\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
"\u001b[0;31mNameError\u001b[0m: name 'z' is not defined"
]
}
],
"source": [
"z"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Instructions conditionnelles"
]
},
{
"cell_type": "code",
"execution_count": 5,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"3\n"
]
}
],
"source": [
"if a > b:\n",
" print(a)\n",
"else:\n",
" print(b)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"### Indentation : espaces ou tabulation ?\n",
"\"Use 4 spaces per indentation level.\", cf. https://www.python.org/dev/peps/pep-0008/"
]
},
{
"cell_type": "code",
"execution_count": 6,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"La valeur de la variable a est supérieure à 1.\n"
]
}
],
"source": [
"if a > 1:\n",
" print('La valeur de la variable a est supérieure à 1.')\n",
"elif a < 1:\n",
" print('La valeur de la variable a est inférieure à 1.')\n",
"else:\n",
" print('La valeur de la variable a est égale à 1.')"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Instructions de bouclage"
]
},
{
"cell_type": "code",
"execution_count": 7,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"1\n",
"2\n",
"3\n",
"4\n",
"5\n"
]
}
],
"source": [
"a = 0\n",
"while a < 5:\n",
" a += 1\n",
" print(a)"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"N.B. : Il n'y a pas de `do...while`, mais l'on peut l'emuler"
]
},
{
"cell_type": "code",
"execution_count": 8,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"1\n",
"2\n",
"3\n",
"4\n",
"5\n"
]
}
],
"source": [
"a = 0\n",
"while True:\n",
" a += 1\n",
" print(a)\n",
" if a >= 5:\n",
" break"
]
},
{
"cell_type": "code",
"execution_count": 9,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"0\n",
"1\n",
"2\n"
]
}
],
"source": [
"for i in range(3):\n",
" print(i)"
]
},
{
"cell_type": "code",
"execution_count": 10,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"0\n",
"1\n",
"2\n"
]
}
],
"source": [
"for i in range(0, 3):\n",
" print(i)"
]
},
{
"cell_type": "code",
"execution_count": 11,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"1\n",
"2\n"
]
}
],
"source": [
"for i in range(1, 3):\n",
" print(i)"
]
},
{
"cell_type": "code",
"execution_count": 12,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"Help on class range in module builtins:\n",
"\n",
"class range(object)\n",
" | range(stop) -> range object\n",
" | range(start, stop[, step]) -> range object\n",
" | \n",
" | Return an object that produces a sequence of integers from start (inclusive)\n",
" | to stop (exclusive) by step. range(i, j) produces i, i+1, i+2, ..., j-1.\n",
" | start defaults to 0, and stop is omitted! range(4) produces 0, 1, 2, 3.\n",
" | These are exactly the valid indices for a list of 4 elements.\n",
" | When step is given, it specifies the increment (or decrement).\n",
" | \n",
" | Methods defined here:\n",
" | \n",
" | __bool__(self, /)\n",
" | self != 0\n",
" | \n",
" | __contains__(self, key, /)\n",
" | Return key in self.\n",
" | \n",
" | __eq__(self, value, /)\n",
" | Return self==value.\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",
" | __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",
" | __ne__(self, value, /)\n",
" | Return self!=value.\n",
" | \n",
" | __reduce__(...)\n",
" | Helper for pickle.\n",
" | \n",
" | __repr__(self, /)\n",
" | Return repr(self).\n",
" | \n",
" | __reversed__(...)\n",
" | Return a reverse iterator.\n",
" | \n",
" | count(...)\n",
" | rangeobject.count(value) -> integer -- return number of occurrences of value\n",
" | \n",
" | index(...)\n",
" | rangeobject.index(value) -> integer -- return index of value.\n",
" | Raise ValueError if the value is not present.\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",
" | ----------------------------------------------------------------------\n",
" | Data descriptors defined here:\n",
" | \n",
" | start\n",
" | \n",
" | step\n",
" | \n",
" | stop\n",
"\n"
]
}
],
"source": [
"help(range)"
]
}
],
"metadata": {
"kernelspec": {
"display_name": "Python 3",
"language": "python",
"name": "python3"
},
"language_info": {
"codemirror_mode": {
"name": "ipython",
"version": 3
},
"file_extension": ".py",
"mimetype": "text/x-python",
"name": "python",
"nbconvert_exporter": "python",
"pygments_lexer": "ipython3",
"version": "3.7.5"
}
},
"nbformat": 4,
"nbformat_minor": 2
}