{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Les ensembles (set)\n",
    "- Les ensembles sont des objets **mutables**. \n",
    "- Ils contiennent des objets qui sont **uniques** et non mutables. Ainsi, un ensemble ne peut pas contenir une liste !\n",
    "- Il n'y a pas d'indexation des valeurs !"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## I) Définition"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### a) Définition directe"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 30,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{1, 2, 3}\n"
     ]
    }
   ],
   "source": [
    "#séquence simple\n",
    "s={1,2,3}\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{1, 2, 3, 5}\n"
     ]
    }
   ],
   "source": [
    "#les répétitions disparaissent\n",
    "s={1,2,3,1,2,2,3,5}\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 28,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "set()\n"
     ]
    }
   ],
   "source": [
    "#définition d'une séquence vide. Attention {} crée un dictionnaire vide.\n",
    "s=set()\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### b) Conversion d'une liste"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[1, 2, 3, 5, 4, 3, 2, 1]\n",
      "{1, 2, 3, 4, 5}\n"
     ]
    }
   ],
   "source": [
    "L=[1,2,3,5,4,3,2,1]\n",
    "s=set(L)\n",
    "print(L)\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### c) Par compréhension"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}\n"
     ]
    }
   ],
   "source": [
    "# Les restes par la division par 13\n",
    "s={x%13 for x in range(1000)}\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## II) Manipulation\n",
    "Il n'y a pas d'indexation des éléments, contrairement aux listes."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}\n"
     ]
    },
    {
     "ename": "TypeError",
     "evalue": "'set' object does not support indexing",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[0;32m<ipython-input-8-22d6c54ebbe9>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0ms\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mset\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mrange\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;36m10\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      2\u001b[0m \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0ms\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 3\u001b[0;31m \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0ms\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;36m2\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mTypeError\u001b[0m: 'set' object does not support indexing"
     ]
    }
   ],
   "source": [
    "s=set(range(10))\n",
    "print(s)\n",
    "print(s[2])"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### a) Parcours par une boucle"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'b', 'c', 'a'}\n",
      "b\n",
      "c\n",
      "a\n"
     ]
    }
   ],
   "source": [
    "# l'ordre est surprenant !\n",
    "s={\"a\",\"b\",\"c\"}\n",
    "print(s)\n",
    "for el in s :\n",
    "    print(el)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### b) Ajout ou suppression"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'d', 'b', 'c', 'a'}\n"
     ]
    }
   ],
   "source": [
    "# ajoute un élément s'il est absent\n",
    "s={\"a\",\"b\",\"c\"}\n",
    "s.add(\"a\") # aucune action ici\n",
    "s.add(\"d\")\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'b', 'c'}\n"
     ]
    }
   ],
   "source": [
    "# enléve un élément s'il est présent\n",
    "s={\"a\",\"b\",\"c\"}\n",
    "s.discard(\"e\") # aucune action ici\n",
    "s.discard(\"a\")\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### c) Union, intersection, diffférence, comparaison"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{1, 2, 3, 4, 5, 6, 7}\n"
     ]
    }
   ],
   "source": [
    "#union de deux ensembles\n",
    "sa={1,2,3,4}\n",
    "sb={3,4,5,6,7}\n",
    "\n",
    "s=sa|sb\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{3, 4}\n"
     ]
    }
   ],
   "source": [
    "#intersection de deux ensembles\n",
    "sa={1,2,3,4}\n",
    "sb={3,4,5,6,7}\n",
    "\n",
    "s=sa&sb\n",
    "print(s)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{1, 2}\n",
      "{5, 6, 7}\n"
     ]
    }
   ],
   "source": [
    "#différence de deux ensembles\n",
    "sa={1,2,3,4}\n",
    "sb={3,4,5,6,7}\n",
    "\n",
    "print(sa-sb)\n",
    "print(sb-sa)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "False\n",
      "True\n"
     ]
    }
   ],
   "source": [
    "#comparaison de deux ensembles\n",
    "sa={3,4}\n",
    "sb={3,4,5,6,7}\n",
    "\n",
    "print(sa==sb) #égalité ?\n",
    "print(sa<sb)  # inclusion ?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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