124 DOUBLE PRECISION FUNCTION zlansy( NORM, UPLO, N, A, LDA, WORK )
136 DOUBLE PRECISION WORK( * )
137 COMPLEX*16 A( lda, * )
143 DOUBLE PRECISION ONE, ZERO
144 parameter ( one = 1.0d+0, zero = 0.0d+0 )
148 DOUBLE PRECISION ABSA, SCALE, SUM, VALUE
151 LOGICAL LSAME, DISNAN
152 EXTERNAL lsame, disnan
164 ELSE IF( lsame( norm,
'M' ) )
THEN
169 IF( lsame( uplo,
'U' ) )
THEN
172 sum = abs( a( i, j ) )
173 IF(
VALUE .LT. sum .OR. disnan( sum ) )
VALUE = sum
179 sum = abs( a( i, j ) )
180 IF(
VALUE .LT. sum .OR. disnan( sum ) )
VALUE = sum
184 ELSE IF( ( lsame( norm,
'I' ) ) .OR. ( lsame( norm,
'O' ) ) .OR.
185 $ ( norm.EQ.
'1' ) )
THEN
190 IF( lsame( uplo,
'U' ) )
THEN
194 absa = abs( a( i, j ) )
196 work( i ) = work( i ) + absa
198 work( j ) = sum + abs( a( j, j ) )
202 IF(
VALUE .LT. sum .OR. disnan( sum ) )
VALUE = sum
209 sum = work( j ) + abs( a( j, j ) )
211 absa = abs( a( i, j ) )
213 work( i ) = work( i ) + absa
215 IF(
VALUE .LT. sum .OR. disnan( sum ) )
VALUE = sum
218 ELSE IF( ( lsame( norm,
'F' ) ) .OR. ( lsame( norm,
'E' ) ) )
THEN
224 IF( lsame( uplo,
'U' ) )
THEN
226 CALL zlassq( j-1, a( 1, j ), 1, scale, sum )
230 CALL zlassq( n-j, a( j+1, j ), 1, scale, sum )
234 CALL zlassq( n, a, lda+1, scale, sum )
235 VALUE = scale*sqrt( sum )
subroutine zlassq(N, X, INCX, SCALE, SUMSQ)
ZLASSQ updates a sum of squares represented in scaled form.
double precision function zlansy(NORM, UPLO, N, A, LDA, WORK)
ZLANSY returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a complex symmetric matrix.