 LAPACK  3.10.0 LAPACK: Linear Algebra PACKage

◆ dlag2s()

 subroutine dlag2s ( integer M, integer N, double precision, dimension( lda, * ) A, integer LDA, real, dimension( ldsa, * ) SA, integer LDSA, integer INFO )

DLAG2S converts a double precision matrix to a single precision matrix.

Purpose:
DLAG2S converts a DOUBLE PRECISION matrix, SA, to a SINGLE
PRECISION matrix, A.

RMAX is the overflow for the SINGLE PRECISION arithmetic
DLAG2S checks that all the entries of A are between -RMAX and
RMAX. If not the conversion is aborted and a flag is raised.

This is an auxiliary routine so there is no argument checking.
Parameters
 [in] M M is INTEGER The number of lines of the matrix A. M >= 0. [in] N N is INTEGER The number of columns of the matrix A. N >= 0. [in] A A is DOUBLE PRECISION array, dimension (LDA,N) On entry, the M-by-N coefficient matrix A. [in] LDA LDA is INTEGER The leading dimension of the array A. LDA >= max(1,M). [out] SA SA is REAL array, dimension (LDSA,N) On exit, if INFO=0, the M-by-N coefficient matrix SA; if INFO>0, the content of SA is unspecified. [in] LDSA LDSA is INTEGER The leading dimension of the array SA. LDSA >= max(1,M). [out] INFO INFO is INTEGER = 0: successful exit. = 1: an entry of the matrix A is greater than the SINGLE PRECISION overflow threshold, in this case, the content of SA in exit is unspecified.

Definition at line 107 of file dlag2s.f.

108 *
109 * -- LAPACK auxiliary routine --
110 * -- LAPACK is a software package provided by Univ. of Tennessee, --
111 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
112 *
113 * .. Scalar Arguments ..
114  INTEGER INFO, LDA, LDSA, M, N
115 * ..
116 * .. Array Arguments ..
117  REAL SA( LDSA, * )
118  DOUBLE PRECISION A( LDA, * )
119 * ..
120 *
121 * =====================================================================
122 *
123 * .. Local Scalars ..
124  INTEGER I, J
125  DOUBLE PRECISION RMAX
126 * ..
127 * .. External Functions ..
128  REAL SLAMCH
129  EXTERNAL slamch
130 * ..
131 * .. Executable Statements ..
132 *
133  rmax = slamch( 'O' )
134  DO 20 j = 1, n
135  DO 10 i = 1, m
136  IF( ( a( i, j ).LT.-rmax ) .OR. ( a( i, j ).GT.rmax ) ) THEN
137  info = 1
138  GO TO 30
139  END IF
140  sa( i, j ) = a( i, j )
141  10 CONTINUE
142  20 CONTINUE
143  info = 0
144  30 CONTINUE
145  RETURN
146 *
147 * End of DLAG2S
148 *
real function slamch(CMACH)
SLAMCH
Definition: slamch.f:68
Here is the caller graph for this function: