93 SUBROUTINE cpttrf( N, D, E, INFO )
112 parameter ( zero = 0.0e+0 )
122 INTRINSIC aimag, cmplx, mod, real
131 CALL xerbla(
'CPTTRF', -info )
144 IF( d( i ).LE.zero )
THEN
149 eii = aimag( e( i ) )
152 e( i ) = cmplx( f, g )
153 d( i+1 ) = d( i+1 ) - f*eir - g*eii
156 DO 110 i = i4+1, n - 4, 4
161 IF( d( i ).LE.zero )
THEN
169 eii = aimag( e( i ) )
172 e( i ) = cmplx( f, g )
173 d( i+1 ) = d( i+1 ) - f*eir - g*eii
175 IF( d( i+1 ).LE.zero )
THEN
182 eir =
REAL( E( I+1 ) )
183 eii = aimag( e( i+1 ) )
186 e( i+1 ) = cmplx( f, g )
187 d( i+2 ) = d( i+2 ) - f*eir - g*eii
189 IF( d( i+2 ).LE.zero )
THEN
196 eir =
REAL( E( I+2 ) )
197 eii = aimag( e( i+2 ) )
200 e( i+2 ) = cmplx( f, g )
201 d( i+3 ) = d( i+3 ) - f*eir - g*eii
203 IF( d( i+3 ).LE.zero )
THEN
210 eir =
REAL( E( I+3 ) )
211 eii = aimag( e( i+3 ) )
214 e( i+3 ) = cmplx( f, g )
215 d( i+4 ) = d( i+4 ) - f*eir - g*eii
subroutine cpttrf(N, D, E, INFO)
CPTTRF
subroutine xerbla(SRNAME, INFO)
XERBLA