dgefa
dgefa - (obsolete) compute the LU factorization of a general matrix A. It is typical to follow
a call to SGEFA with a call to SGESL to solve Ax = b or to SGEDI to compute the determinant of A.
SUBROUTINE DGEFA( A, LDA, N, IPIVOT, INFO)
INTEGER LDA, N, INFO
INTEGER IPIVOT(*)
DOUBLE PRECISION A(LDA,*)
SUBROUTINE DGEFA_64( A, LDA, N, IPIVOT, INFO)
INTEGER*8 LDA, N, INFO
INTEGER*8 IPIVOT(*)
DOUBLE PRECISION A(LDA,*)
#include <sunperf.h>
void dgefa(double *a, int lda, int n, int *ipivot, int *info);
void dgefa_64(double *a, long lda, long n, long *ipivot, long *info);
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* A (input/output)
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On entry, the matrix A.
On exit, an LU factorization of A.
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* LDA (input)
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Leading dimension of the array A as specified in a dimension or type statement. LDA >= max(1,N).
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* N (input)
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Order of the matrix A. N >= 0.
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* IPIVOT (output)
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On exit, a vector of pivot indices.
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* INFO (output)
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On exit:
INFO = 0 Subroutine completed normally.
INFO > 0 Returns a value k if U(k,k) = 0 to indicate that SGESL will divide by zero if called.