SPOSL(3F)
SPOSL - SPOSL solves the real symmetric positive definite system A * X = B using the factors computed by SPOCO or SPOFA.
As shipped in IRIX 6.5.22. Unchanged since IRIX 6.5.
NAME SPOSL - SPOSL solves the real symmetric positive definite system A * X = B using the factors computed by SPOCO or SPOFA. SYNOPSYS SUBROUTINE SPOSL(A,LDA,N,B) DESCRIPTION On Entry A REAL(LDA, N) the output from SPOCO or SPOFA. LDA INTEGER the leading dimension of the array A . N INTEGER the order of the matrix A . B REAL(N) the right hand side vector. 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 usually caused by improper subroutine arguments. It will not occur if the subroutines are called correctly and INFO .EQ. 0 . To compute INVERSE(A) * C where C is a matrix with P columns CALL SPOCO(A,LDA,N,RCOND,Z,INFO) IF (RCOND is too small .OR. INFO .NE. 0) GO TO ... DO 10 J = 1, P CALL SPOSL(A,LDA,N,C(1,J)) 10 CONTINUE LINPACK. This version dated 08/14/78 . Cleve Moler, University of New Mexico, Argonne National Lab. Subroutines and Functions BLAS SAXPY,SDOT