CGESL(3F)CGESL(3F)NAMECGESL - CGESL solves the complex system A * X = B or CTRANS(A) * X =
B using the factors computed by CGECO or CGEFA.
SYNOPSYS
SUBROUTINE CGESL(A,LDA,N,IPVT,B,JOB)
DESCRIPTION
On Entry
A COMPLEX(LDA, N)
the output from CGECO or CGEFA.
LDA INTEGER
the leading dimension of the array A .
N INTEGER
the order of the matrix A .
IPVT INTEGER(N)
the pivot vector from CGECO or CGEFA.
B COMPLEX(N)
the right hand side vector.
JOB INTEGER
= 0 to solve A*X = B ,
= nonzero to solve CTRANS(A)*X = B where
CTRANS(A) is the conjugate transpose. On Return
B the solution vector X . Error Condition
A division by zero will occur if the input factor contains a zero on the
diagonal. Technically this indicates singularity but it is often caused
by improper arguments or improper setting of LDA . It will not occur if
the subroutines are called correctly and if CGECO has set RCOND .GT. 0.0
or CGEFA has set INFO .EQ. 0 . To compute INVERSE(A) * C where C is
a matrix with P columns
CALL CGECO(A,LDA,N,IPVT,RCOND,Z)
IF (RCOND is too small) GO TO ...
DO 10 J = 1, P
CALL CGESL(A,LDA,N,IPVT,C(1,J),0) 10 CONTINUE LINPACK. This version
dated 08/14/78 . Cleve Moler, University of New Mexico, Argonne National
Lab. Subroutines and Functions BLAS CAXPY,CDOTC Fortran CONJG
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