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comparison liboctave/dMatrix.cc @ 10805:8c858a1a2079

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simplify Matrix::extract
author Jaroslav Hajek <highegg@gmail.com>
date Tue, 20 Jul 2010 12:56:05 +0200
parents 832732c2eb80
children 7c542263a92a
comparison
equal deleted inserted replaced
10804:3d5c6b84ddaf 10805:8c858a1a2079
578 Matrix::extract (octave_idx_type r1, octave_idx_type c1, octave_idx_type r2, octave_idx_type c2) const 578 Matrix::extract (octave_idx_type r1, octave_idx_type c1, octave_idx_type r2, octave_idx_type c2) const
579 { 579 {
580 if (r1 > r2) { octave_idx_type tmp = r1; r1 = r2; r2 = tmp; } 580 if (r1 > r2) { octave_idx_type tmp = r1; r1 = r2; r2 = tmp; }
581 if (c1 > c2) { octave_idx_type tmp = c1; c1 = c2; c2 = tmp; } 581 if (c1 > c2) { octave_idx_type tmp = c1; c1 = c2; c2 = tmp; }
582 582
583 octave_idx_type new_r = r2 - r1 + 1; 583 return index (idx_vector (r1, r2+1), idx_vector (c1, c2+1));
584 octave_idx_type new_c = c2 - c1 + 1;
585
586 Matrix result (new_r, new_c);
587
588 for (octave_idx_type j = 0; j < new_c; j++)
589 for (octave_idx_type i = 0; i < new_r; i++)
590 result.xelem (i, j) = elem (r1+i, c1+j);
591
592 return result;
593 } 584 }
594 585
595 Matrix 586 Matrix
596 Matrix::extract_n (octave_idx_type r1, octave_idx_type c1, octave_idx_type nr, octave_idx_type nc) const 587 Matrix::extract_n (octave_idx_type r1, octave_idx_type c1, octave_idx_type nr, octave_idx_type nc) const
597 { 588 {
598 Matrix result (nr, nc); 589 return index (idx_vector (r1, r1 + nr), idx_vector (r2, r2 + nr));
599
600 for (octave_idx_type j = 0; j < nc; j++)
601 for (octave_idx_type i = 0; i < nr; i++)
602 result.xelem (i, j) = elem (r1+i, c1+j);
603
604 return result;
605 } 590 }
606 591
607 // extract row or column i. 592 // extract row or column i.
608 593
609 RowVector 594 RowVector