DTRSL(3F) DTRSL(3F)
DTRSL  DTRSL solves systems of the form
T * X = B or
TRANS(T) * X = B
where T is a triangular matrix of order N. Here TRANS(T) denotes the
transpose of the matrix T.
SUBROUTINE DTRSL(T,LDT,N,B,JOB,INFO)
On Entry
T DOUBLE PRECISION(LDT,N)
T contains the matrix of the system. 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.
B DOUBLE PRECISION(N).
B contains the right hand side of the system.
JOB INTEGER
JOB specifies what kind of system is to be solved.
If JOB is
00 solve T*X=B, T lower triangular,
01 solve T*X=B, T upper triangular,
10 solve TRANS(T)*X=B, T lower triangular,
11 solve TRANS(T)*X=B, T upper triangular. On Return
B B contains the solution, if INFO .EQ. 0.
Otherwise B is unaltered.
INFO INTEGER
INFO contains zero if the system is nonsingular.
Otherwise INFO contains the index of
the first zero diagonal element of T. LINPACK. This version dated
08/14/78 . G. W. Stewart, University of Maryland, Argonne National Lab.
Subroutines and Functions BLAS DAXPY,DDOT Fortran MOD
PPPPaaaaggggeeee 1111 [ Back ]
