version 1.20, 2020/05/21 21:45:57
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version 1.21, 2023/08/07 08:38:51
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*> \author Univ. of Colorado Denver |
*> \author Univ. of Colorado Denver |
*> \author NAG Ltd. |
*> \author NAG Ltd. |
* |
* |
*> \date November 2017 |
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* |
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*> \ingroup doubleOTHERcomputational |
*> \ingroup doubleOTHERcomputational |
* |
* |
*> \par Further Details: |
*> \par Further Details: |
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SUBROUTINE DGSVJ0( JOBV, M, N, A, LDA, D, SVA, MV, V, LDV, EPS, |
SUBROUTINE DGSVJ0( JOBV, M, N, A, LDA, D, SVA, MV, V, LDV, EPS, |
$ SFMIN, TOL, NSWEEP, WORK, LWORK, INFO ) |
$ SFMIN, TOL, NSWEEP, WORK, LWORK, INFO ) |
* |
* |
* -- LAPACK computational routine (version 3.8.0) -- |
* -- LAPACK computational routine -- |
* -- LAPACK is a software package provided by Univ. of Tennessee, -- |
* -- LAPACK is a software package provided by Univ. of Tennessee, -- |
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
* November 2017 |
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* |
* |
* .. Scalar Arguments .. |
* .. Scalar Arguments .. |
INTEGER INFO, LDA, LDV, LWORK, M, MV, N, NSWEEP |
INTEGER INFO, LDA, LDV, LWORK, M, MV, N, NSWEEP |
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* Some BLAS implementations compute DNRM2(M,A(1,p),1) |
* Some BLAS implementations compute DNRM2(M,A(1,p),1) |
* as DSQRT(DDOT(M,A(1,p),1,A(1,p),1)), which may result in |
* as DSQRT(DDOT(M,A(1,p),1,A(1,p),1)), which may result in |
* overflow for ||A(:,p)||_2 > DSQRT(overflow_threshold), and |
* overflow for ||A(:,p)||_2 > DSQRT(overflow_threshold), and |
* undeflow for ||A(:,p)||_2 < DSQRT(underflow_threshold). |
* underflow for ||A(:,p)||_2 < DSQRT(underflow_threshold). |
* Hence, DNRM2 cannot be trusted, not even in the case when |
* Hence, DNRM2 cannot be trusted, not even in the case when |
* the true norm is far from the under(over)flow boundaries. |
* the true norm is far from the under(over)flow boundaries. |
* If properly implemented DNRM2 is available, the IF-THEN-ELSE |
* If properly implemented DNRM2 is available, the IF-THEN-ELSE |