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  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Les dictionnaires\n",
    "- Les dictionnaires sont des objets **mutables**.\n",
    "- Ce sont des ensembles de couples **clés/valeurs**.\n",
    "- L'accès aux valeurs se fait par les clés qui sont donc uniques."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## I) Définition"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### a) Définition simple"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'x': 3, 'y': 5, 'z': [1, 3]}\n"
     ]
    }
   ],
   "source": [
    "#la façon la plus rapide\n",
    "d=dict(x=3,y=5,z=1)\n",
    "print(d)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'x': 3, 'y': 5, 'z': 1}\n"
     ]
    }
   ],
   "source": [
    "# en rentrant les couples de clés et de valeurs.\n",
    "d={\"x\":3,\"y\":5,\"z\":1}\n",
    "print(d)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{}\n"
     ]
    }
   ],
   "source": [
    "# un dictionnaire vide\n",
    "d=dict()\n",
    "print(d)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### b) À partir d'une liste de tuples"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'x': 3, 'y': 5, 'z': 1}\n"
     ]
    }
   ],
   "source": [
    "L=[(\"x\",3),(\"y\",5),(\"z\",1)]\n",
    "d=dict(L)\n",
    "print(d)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## II) Accès aux éléments"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "x 3\n",
      "y 5\n",
      "z 1\n"
     ]
    }
   ],
   "source": [
    "# accès aux couples clés,valeurs\n",
    "d=dict(x=3,y=5,z=1)\n",
    "for c,e in d.items():\n",
    "    print(c,e)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "x\n",
      "y\n",
      "z\n"
     ]
    }
   ],
   "source": [
    "# accès aux clés uniquement\n",
    "d=dict(x=3,y=5,z=1)\n",
    "for c in d.keys():\n",
    "    print(c)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "3\n",
      "5\n",
      "1\n"
     ]
    }
   ],
   "source": [
    "# accès aux valeurs uniquement\n",
    "d=dict(x=3,y=5,z=1)\n",
    "for e in d.values():\n",
    "    print(e)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "5\n"
     ]
    }
   ],
   "source": [
    "# accès à une valeur à partir de la clé\n",
    "d=dict(x=3,y=5,z=1)\n",
    "val=d.get(\"y\")\n",
    "print(val)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "None\n",
      "0\n"
     ]
    }
   ],
   "source": [
    "# accès à une valeur à partir de la clé avec valeur par défaut si valeur absente\n",
    "d=dict(x=3,y=5,z=1)\n",
    "val=d.get(\"w\")\n",
    "print(val)\n",
    "val=d.get(\"w\",0)\n",
    "print(val)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## III) Modification ou ajout de valeurs"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'x': 77, 'y': 5, 'z': 1}\n"
     ]
    }
   ],
   "source": [
    "# La clé existant, on modifie la valeur\n",
    "d=dict(x=3,y=5,z=1)\n",
    "d[\"x\"]=77\n",
    "print(d)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'x': 3, 'y': 5, 'z': 1, 'w': 10}\n"
     ]
    }
   ],
   "source": [
    "# La clé étant absente, on ajoute une entrée\n",
    "d=dict(x=3,y=5,z=1)\n",
    "d[\"w\"]=10\n",
    "print(d)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'x': 77, 'y': 5, 'z': 1, 'a': 5, 'b': 8}\n"
     ]
    }
   ],
   "source": [
    "# On met à jour à partir d'un autre dictionnaire\n",
    "d=dict(x=3,y=5,z=1)\n",
    "delta=dict(a=5,b=8,x=77)\n",
    "d.update(delta)\n",
    "print(d)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
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   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  },
  {
   "cell_type": "code",
   "execution_count": null,
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