CTRDI(3F)CTRDI(3F)NAMECTRDI - CTRDI computes the determinant and inverse of a complex
triangular matrix.
SYNOPSYS
SUBROUTINE CTRDI(T,LDT,N,DET,JOB,INFO)
DESCRIPTION
On Entry
T COMPLEX(LDT,N)
T contains the triangular matrix. The zero
elements of the matrix are not referenced, and
the corresponding elements of the array can be
used to store other information.
LDT INTEGER
LDT is the leading dimension of the array T.
N INTEGER
N is the order of the system.
JOB INTEGER
= 010 no det, inverse of lower triangular.
= 011 no det, inverse of upper triangular.
= 100 det, no inverse.
= 110 det, inverse of lower triangular.
= 111 det, inverse of upper triangular. On Return
T inverse of original matrix if requested.
Otherwise unchanged.
DET COMPLEX(2)
determinant of original matrix if requested.
Otherwise not referenced.
Determinant = DET(1) * 10.0**DET(2)
with 1.0 .LE. CABS1(DET(1)) .LT. 10.0
or DET(1) .EQ. 0.0 .
INFO INTEGER
INFO contains zero if the system is nonsingular
and the inverse is requested.
Otherwise INFO contains the index of
a zero diagonal element of T. LINPACK. This version dated 08/14/78 .
Cleve Moler, University of New Mexico, Argonne National Lab. Subroutines
and Functions BLAS CAXPY,CSCAL Fortran ABS,AIMAG,CMPLX,MOD,REAL
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