121 DOUBLE PRECISION FUNCTION dlansy( NORM, UPLO, N, A, LDA, WORK )
132 DOUBLE PRECISION a( lda, * ), work( * )
138 DOUBLE PRECISION one, zero
139 parameter( one = 1.0d+0, zero = 0.0d+0 )
143 DOUBLE PRECISION absa, scale, sum, value
159 ELSE IF(
lsame( norm,
'M' ) )
THEN
164 IF(
lsame( uplo,
'U' ) )
THEN
167 sum = abs( a( i, j ) )
168 IF(
VALUE .LT. sum .OR.
disnan( sum ) )
VALUE = sum
174 sum = abs( a( i, j ) )
175 IF(
VALUE .LT. sum .OR.
disnan( sum ) )
VALUE = sum
179 ELSE IF( (
lsame( norm,
'I' ) ) .OR. (
lsame( norm,
'O' ) ) .OR.
180 $ ( norm.EQ.
'1' ) )
THEN
185 IF(
lsame( uplo,
'U' ) )
THEN
189 absa = abs( a( i, j ) )
191 work( i ) = work( i ) + absa
193 work( j ) = sum + abs( a( j, j ) )
197 IF(
VALUE .LT. sum .OR.
disnan( sum ) )
VALUE = sum
204 sum = work( j ) + abs( a( j, j ) )
206 absa = abs( a( i, j ) )
208 work( i ) = work( i ) + absa
210 IF(
VALUE .LT. sum .OR.
disnan( sum ) )
VALUE = sum
213 ELSE IF( (
lsame( norm,
'F' ) ) .OR. (
lsame( norm,
'E' ) ) )
THEN
219 IF(
lsame( uplo,
'U' ) )
THEN
221 CALL dlassq( j-1, a( 1, j ), 1, scale, sum )
225 CALL dlassq( n-j, a( j+1, j ), 1, scale, sum )
229 CALL dlassq( n, a, lda+1, scale, sum )
230 VALUE = scale*sqrt( sum )
logical function disnan(din)
DISNAN tests input for NaN.
double precision function dlansy(norm, uplo, n, a, lda, work)
DLANSY returns the value of the 1-norm, or the Frobenius norm, or the infinity norm,...
subroutine dlassq(n, x, incx, scale, sumsq)
DLASSQ updates a sum of squares represented in scaled form.
logical function lsame(ca, cb)
LSAME