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Removed double[][] solve(double[][]) from LUDecompositionImpl.Solver 

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1166963 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Sebastien Brisard 2011-09-09 02:13:03 +00:00
parent 4a73dfc4fe
commit ac3c66add4
1 changed files with 50 additions and 1 deletions
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51
src/main/java/org/apache/commons/math/linear/LUDecompositionImpl.java
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@ -340,7 +340,56 @@ public class LUDecompositionImpl implements LUDecomposition {
/** {@inheritDoc} */
public RealMatrix solve(RealMatrix b) {
return new Array2DRowRealMatrix(solve(b.getData()), false);
final int m = pivot.length;
if (b.getRowDimension() != m) {
throw new DimensionMismatchException(b.getRowDimension(), m);
}
if (singular) {
throw new SingularMatrixException();
}
final int nColB = b.getColumnDimension();
// Apply permutations to b
final double[][] bp = new double[m][nColB];
for (int row = 0; row < m; row++) {
final double[] bpRow = bp[row];
final int pRow = pivot[row];
for (int col = 0; col < nColB; col++) {
bpRow[col] = b.getEntry(pRow, col);
}
}
// Solve LY = b
for (int col = 0; col < m; col++) {
final double[] bpCol = bp[col];
for (int i = col + 1; i < m; i++) {
final double[] bpI = bp[i];
final double luICol = lu[i][col];
for (int j = 0; j < nColB; j++) {
bpI[j] -= bpCol[j] * luICol;
}
}
}
// Solve UX = Y
for (int col = m - 1; col >= 0; col--) {
final double[] bpCol = bp[col];
final double luDiag = lu[col][col];
for (int j = 0; j < nColB; j++) {
bpCol[j] /= luDiag;
}
for (int i = 0; i < col; i++) {
final double[] bpI = bp[i];
final double luICol = lu[i][col];
for (int j = 0; j < nColB; j++) {
bpI[j] -= bpCol[j] * luICol;
}
}
}
return new Array2DRowRealMatrix(bp, false);
}
/** {@inheritDoc} */