回答編集履歴
1
修正箇所の追加
test
CHANGED
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@@ -11,3 +11,87 @@
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`double t = b[k]; b[k] = b[m]; b[m] = t;`
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**追記**
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```C
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/* 前進消去（ピボット選択）*/
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for(k = 0; k < N-1; k++){ /* 第ｋステップ */
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m = k;
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mmax = fabs(*(ak+k));
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ai = ak; // ★
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for(i = k+1; i < N; i++){ /* ピボット選択 */
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ai += N; // ★
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if(fabs(*(ai+k)) > mmax){ // ★
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m = i;
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mmax = fabs(*(ai+k)); // ★
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}
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}
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printf("column %d: row %d is max\n", k, m);
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if(m != k){ /* 第ｋ行と第m行を交換 */
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double *am = A + m*N; // ★
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for(i = k; i < N; i++){/* 係数行列 */
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temp = *(ak+i);
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*(ak+i) = *(am+i); // ★
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*(am+i) = temp; // ★
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}
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/* 既知ベクトル */
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temp = b[k];
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b[k] = b[m];
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b[m] = temp;
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}
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/* 第k列消去 */
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ai = ak; // ★
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for (i = k + 1; i < N; i++){
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ai += N; // ★
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r = *(ai+k) / *(ak+k); // ★
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for (j = k; j < N; j++){
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*(ai+j) -= *(ak+j) * r; // ★
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}
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b[i] -= b[k] * r;
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}
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PrintAb(A, b, N);
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ak+=N;
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}
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```
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