2016-11-29 Parcours de tableaux.ipynb

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    "def tabmin(tab):\n",
    "    \"\"\"\n",
    "    :entrée tab: tableau de float\n",
    "    :pré-cond: len(tab) > 0\n",
    "    :sortie imin: int\n",
    "    :post-cond: imin est l'indice de la plus petite valeur\n",
    "                de tab\n",
    "    \"\"\"\n",
    "    imin = 0\n",
    "    vmin = tab[imin]\n",
    "    i = 1\n",
    "    while i < len(tab):\n",
    "        if tab[i] < vmin:\n",
    "            imin = i\n",
    "            vmin = tab[imin]\n",
    "        i = i+1\n",
    "    return imin\n",
    "\n",
    "# NB: on peut aussi se passer de la variable vmin,\n",
    "# puisqu'elle est à tout moment égale à tab[imin]\n",
    "\n",
    "def tabmin(tab):\n",
    "    \"\"\"\n",
    "    :entrée tab: tableau de float\n",
    "    :pré-cond: len(tab) > 0\n",
    "    :sortie imin: int\n",
    "    :post-cond: imin est l'indice de la plus petite valeur\n",
    "                de tab\n",
    "    \"\"\"\n",
    "    imin = 0\n",
    "    i = 1\n",
    "    while i < len(tab):\n",
    "        if tab[i] < tab[imin]:\n",
    "            imin = i\n",
    "        i = i+1\n",
    "    return imin\n",
    "\n",
    "print(tabmin(array([5,6,7,8,9])))\n",
    "print(tabmin(array([9,8,7,6,5])))\n",
    "print(tabmin(array([9,5,8,6,7])))"
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    "# NB: le contrat est sous-spécifié en cas d'ex-aequo\n",
    "# notre algo retourne le plus petit indice du minimum\n",
    "\n",
    "print(tabmin(array([9,8,9,8,9])))\n",
    "print(tabmin(array([9,9,9,9,9])))"
   ]
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   "source": [
    "def indice_val(tab, val):\n",
    "    \"\"\"\n",
    "    :entrée tab: tableau de float\n",
    "    :entrée val: float\n",
    "    :sortie ival: int\n",
    "    :post-cond: ival est le plus petit indice tel que\n",
    "                tab[ival] = val,\n",
    "                -1 si val n'est pas dans tab\n",
    "    \"\"\"\n",
    "    ival = -1\n",
    "    i = 0\n",
    "    while i < len(tab)  and  ival == -1:\n",
    "        if tab[i] == val:\n",
    "            ival = i\n",
    "        i = i+1\n",
    "    return ival\n",
    "\n",
    "print(indice_val(array([10,11,12,13,14,10]), 11))\n",
    "print(indice_val(array([10,11,12,13,14,10]), 12))\n",
    "print(indice_val(array([10,11,12,13,14,10]), 10))\n",
    "print(indice_val(array([10,11,12,13,14,10]), 16))"
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