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    1:       SUBROUTINE ZLAG2C( M, N, A, LDA, SA, LDSA, INFO )
    2: *
    3: *  -- LAPACK PROTOTYPE auxiliary routine (version 3.1.2) --
    4: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
    5: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
    6: *     August 2007
    7: *
    8: *     ..
    9: *     .. Scalar Arguments ..
   10:       INTEGER            INFO, LDA, LDSA, M, N
   11: *     ..
   12: *     .. Array Arguments ..
   13:       COMPLEX            SA( LDSA, * )
   14:       COMPLEX*16         A( LDA, * )
   15: *     ..
   16: *
   17: *  Purpose
   18: *  =======
   19: *
   20: *  ZLAG2C converts a COMPLEX*16 matrix, SA, to a COMPLEX matrix, A.
   21: *
   22: *  RMAX is the overflow for the SINGLE PRECISION arithmetic
   23: *  ZLAG2C checks that all the entries of A are between -RMAX and
   24: *  RMAX. If not the convertion is aborted and a flag is raised.
   25: *
   26: *  This is an auxiliary routine so there is no argument checking.
   27: *
   28: *  Arguments
   29: *  =========
   30: *
   31: *  M       (input) INTEGER
   32: *          The number of lines of the matrix A.  M >= 0.
   33: *
   34: *  N       (input) INTEGER
   35: *          The number of columns of the matrix A.  N >= 0.
   36: *
   37: *  A       (input) COMPLEX*16 array, dimension (LDA,N)
   38: *          On entry, the M-by-N coefficient matrix A.
   39: *
   40: *  LDA     (input) INTEGER
   41: *          The leading dimension of the array A.  LDA >= max(1,M).
   42: *
   43: *  SA      (output) COMPLEX array, dimension (LDSA,N)
   44: *          On exit, if INFO=0, the M-by-N coefficient matrix SA; if
   45: *          INFO>0, the content of SA is unspecified.
   46: *
   47: *  LDSA    (input) INTEGER
   48: *          The leading dimension of the array SA.  LDSA >= max(1,M).
   49: *
   50: *  INFO    (output) INTEGER
   51: *          = 0:  successful exit.
   52: *          = 1:  an entry of the matrix A is greater than the SINGLE
   53: *                PRECISION overflow threshold, in this case, the content
   54: *                of SA in exit is unspecified.
   55: *
   56: *  =========
   57: *
   58: *     .. Local Scalars ..
   59:       INTEGER            I, J
   60:       DOUBLE PRECISION   RMAX
   61: *     ..
   62: *     .. Intrinsic Functions ..
   63:       INTRINSIC          DBLE, DIMAG
   64: *     ..
   65: *     .. External Functions ..
   66:       REAL               SLAMCH
   67:       EXTERNAL           SLAMCH
   68: *     ..
   69: *     .. Executable Statements ..
   70: *
   71:       RMAX = SLAMCH( 'O' )
   72:       DO 20 J = 1, N
   73:          DO 10 I = 1, M
   74:             IF( ( DBLE( A( I, J ) ).LT.-RMAX ) .OR.
   75:      +          ( DBLE( A( I, J ) ).GT.RMAX ) .OR.
   76:      +          ( DIMAG( A( I, J ) ).LT.-RMAX ) .OR.
   77:      +          ( DIMAG( A( I, J ) ).GT.RMAX ) ) THEN
   78:                INFO = 1
   79:                GO TO 30
   80:             END IF
   81:             SA( I, J ) = A( I, J )
   82:    10    CONTINUE
   83:    20 CONTINUE
   84:       INFO = 0
   85:    30 CONTINUE
   86:       RETURN
   87: *
   88: *     End of ZLAG2C
   89: *
   90:       END