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SUBROUTINE ZLAG2C( M, N, A, LDA, SA, LDSA, INFO )
*
* -- LAPACK PROTOTYPE auxiliary routine (version 3.1.2) --
* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
* August 2007
*
* ..
* .. Scalar Arguments ..
INTEGER INFO, LDA, LDSA, M, N
* ..
* .. Array Arguments ..
COMPLEX SA( LDSA, * )
COMPLEX*16 A( LDA, * )
* ..
*
* Purpose
* =======
*
* ZLAG2C converts a COMPLEX*16 matrix, SA, to a COMPLEX matrix, A.
*
* RMAX is the overflow for the SINGLE PRECISION arithmetic
* ZLAG2C checks that all the entries of A are between -RMAX and
* RMAX. If not the convertion is aborted and a flag is raised.
*
* This is an auxiliary routine so there is no argument checking.
*
* Arguments
* =========
*
* M (input) INTEGER
* The number of lines of the matrix A. M >= 0.
*
* N (input) INTEGER
* The number of columns of the matrix A. N >= 0.
*
* A (input) COMPLEX*16 array, dimension (LDA,N)
* On entry, the M-by-N coefficient matrix A.
*
* LDA (input) INTEGER
* The leading dimension of the array A. LDA >= max(1,M).
*
* SA (output) COMPLEX 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.
*
* LDSA (input) INTEGER
* The leading dimension of the array SA. LDSA >= max(1,M).
*
* INFO (output) 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.
*
* =========
*
* .. Local Scalars ..
INTEGER I, J
DOUBLE PRECISION RMAX
* ..
* .. Intrinsic Functions ..
INTRINSIC DBLE, DIMAG
* ..
* .. External Functions ..
REAL SLAMCH
EXTERNAL SLAMCH
* ..
* .. Executable Statements ..
*
RMAX = SLAMCH( 'O' )
DO 20 J = 1, N
DO 10 I = 1, M
IF( ( DBLE( A( I, J ) ).LT.-RMAX ) .OR.
+ ( DBLE( A( I, J ) ).GT.RMAX ) .OR.
+ ( DIMAG( A( I, J ) ).LT.-RMAX ) .OR.
+ ( DIMAG( A( I, J ) ).GT.RMAX ) ) THEN
INFO = 1
GO TO 30
END IF
SA( I, J ) = A( I, J )
10 CONTINUE
20 CONTINUE
INFO = 0
30 CONTINUE
RETURN
*
* End of ZLAG2C
*
END
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