LAPACK 3.11.0 LAPACK: Linear Algebra PACKage
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## ◆ 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, A, to a SINGLE
PRECISION matrix, SA.

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* .. Intrinsic Functions ..
132 INTRINSIC real
133* ..
134* .. Executable Statements ..
135*
136 rmax = slamch( 'O' )
137 DO 20 j = 1, n
138 DO 10 i = 1, m
139 IF( ( a( i, j ).LT.-rmax ) .OR. ( a( i, j ).GT.rmax ) ) THEN
140 info = 1
141 GO TO 30
142 END IF
143 sa( i, j ) = real( a( i, j ) )
144 10 CONTINUE
145 20 CONTINUE
146 info = 0
147 30 CONTINUE
148 RETURN
149*
150* End of DLAG2S
151*
real function slamch(CMACH)
SLAMCH
Definition: slamch.f:68
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