Fix gauss_jordan_elimination.ipynb

Author: chvmvd

static/gaussian-elimination/gauss_jordan_elimination.ipynb

@@ -10,25 +10,31 @@
     "    # 前進消去\n",
     "    for i in range(len(a)):\n",
     "        # 部分ピボット選択\n",
+    "        max_index = i\n",
     "        for j in range(i + 1, len(a)):\n",
-    "            if abs(a[i][i]) < abs(a[j][i]):\n",
-    "                a[i], a[j] = a[j], a[i]\n",
+    "            if abs(a[max_index][i]) < abs(a[j][i]):\n",
+    "                max_index = j\n",
+    "                a[i], a[max_index] = a[max_index], a[i]\n",
     "\n",
     "        # pivot倍で行を割る\n",
     "        pivot = a[i][i]\n",
     "        for j in range(i, len(a[i])):\n",
     "            a[i][j] /= pivot\n",
     "\n",
+    "        # highlight-start\n",
     "        # 掃き出す\n",
     "        for j in range(len(a)):\n",
     "            if j != i:\n",
     "                factor = a[j][i]\n",
     "                for k in range(i, len(a[i])):\n",
     "                    a[j][k] -= factor * a[i][k]\n",
+    "        # highlight-end\n",
+    "    # highlight-start\n",
     "    x = []\n",
     "    for i in range(len(a)):\n",
     "        x.append(a[i][len(a[i]) - 1])\n",
     "    return x\n",
+    "    # highlight-end\n",
     "\n",
     "\n",
     "print(gauss_jordan_elimination([[0, -2, 3, 2], [-1, 3, -2, 1], [1, -1, 6, 11]]))"