173 SUBROUTINE cla_geamv( TRANS, M, N, ALPHA, A, LDA, X, INCX, BETA,
182 INTEGER INCX, INCY, LDA, M, N
186 COMPLEX A( LDA, * ), X( * )
194 parameter( one = 1.0e+0, zero = 0.0e+0 )
199 INTEGER I, INFO, IY, J, JX, KX, KY, LENX, LENY
211 INTRINSIC max, abs, real, aimag, sign
217 cabs1( cdum ) = abs( real( cdum ) ) + abs( aimag( cdum ) )
224 IF ( .NOT.( ( trans.EQ.ilatrans(
'N' ) )
225 $ .OR. ( trans.EQ.ilatrans(
'T' ) )
226 $ .OR. ( trans.EQ.ilatrans(
'C' ) ) ) )
THEN
228 ELSE IF( m.LT.0 )
THEN
230 ELSE IF( n.LT.0 )
THEN
232 ELSE IF( lda.LT.max( 1, m ) )
THEN
234 ELSE IF( incx.EQ.0 )
THEN
236 ELSE IF( incy.EQ.0 )
THEN
240 CALL xerbla(
'CLA_GEAMV ', info )
246 IF( ( m.EQ.0 ).OR.( n.EQ.0 ).OR.
247 $ ( ( alpha.EQ.zero ).AND.( beta.EQ.one ) ) )
253 IF( trans.EQ.ilatrans(
'N' ) )
THEN
263 kx = 1 - ( lenx - 1 )*incx
268 ky = 1 - ( leny - 1 )*incy
274 safe1 = slamch(
'Safe minimum' )
284 IF ( incx.EQ.1 )
THEN
285 IF( trans.EQ.ilatrans(
'N' ) )
THEN
287 IF ( beta .EQ. 0.0 )
THEN
290 ELSE IF ( y( iy ) .EQ. 0.0 )
THEN
294 y( iy ) = beta * abs( y( iy ) )
296 IF ( alpha .NE. 0.0 )
THEN
298 temp = cabs1( a( i, j ) )
299 symb_zero = symb_zero .AND.
300 $ ( x( j ) .EQ. zero .OR. temp .EQ. zero )
302 y( iy ) = y( iy ) + alpha*cabs1( x( j ) )*temp
306 IF ( .NOT.symb_zero ) y( iy ) =
307 $ y( iy ) + sign( safe1, y( iy ) )
313 IF ( beta .EQ. 0.0 )
THEN
316 ELSE IF ( y( iy ) .EQ. 0.0 )
THEN
320 y( iy ) = beta * abs( y( iy ) )
322 IF ( alpha .NE. 0.0 )
THEN
324 temp = cabs1( a( j, i ) )
325 symb_zero = symb_zero .AND.
326 $ ( x( j ) .EQ. zero .OR. temp .EQ. zero )
328 y( iy ) = y( iy ) + alpha*cabs1( x( j ) )*temp
332 IF ( .NOT.symb_zero ) y( iy ) =
333 $ y( iy ) + sign( safe1, y( iy ) )
339 IF( trans.EQ.ilatrans(
'N' ) )
THEN
341 IF ( beta .EQ. 0.0 )
THEN
344 ELSE IF ( y( iy ) .EQ. 0.0 )
THEN
348 y( iy ) = beta * abs( y( iy ) )
350 IF ( alpha .NE. 0.0 )
THEN
353 temp = cabs1( a( i, j ) )
354 symb_zero = symb_zero .AND.
355 $ ( x( jx ) .EQ. zero .OR. temp .EQ. zero )
357 y( iy ) = y( iy ) + alpha*cabs1( x( jx ) )*temp
362 IF ( .NOT.symb_zero ) y( iy ) =
363 $ y( iy ) + sign( safe1, y( iy ) )
369 IF ( beta .EQ. 0.0 )
THEN
372 ELSE IF ( y( iy ) .EQ. 0.0 )
THEN
376 y( iy ) = beta * abs( y( iy ) )
378 IF ( alpha .NE. 0.0 )
THEN
381 temp = cabs1( a( j, i ) )
382 symb_zero = symb_zero .AND.
383 $ ( x( jx ) .EQ. zero .OR. temp .EQ. zero )
385 y( iy ) = y( iy ) + alpha*cabs1( x( jx ) )*temp
390 IF ( .NOT.symb_zero ) y( iy ) =
391 $ y( iy ) + sign( safe1, y( iy ) )
subroutine xerbla(SRNAME, INFO)
XERBLA
integer function ilatrans(TRANS)
ILATRANS
subroutine cla_geamv(TRANS, M, N, ALPHA, A, LDA, X, INCX, BETA, Y, INCY)
CLA_GEAMV computes a matrix-vector product using a general matrix to calculate error bounds.
real function slamch(CMACH)
SLAMCH