C lssinfo: C C 0: Success. C 1: Matrix not positive definite. C 2: Rank deficient matrix. C 6: Insufficient space to store the linear system. C 7: Insufficient double precision working space. C 8: Insufficient integer working space. C ****************************************************************** C ****************************************************************** logical function lss(lsssub) C SCALAR ARGUMENTS character * 4 lsssub lss = .false. return end C ****************************************************************** C ****************************************************************** subroutine lssini(sclsys,acneig,usefac) implicit none C SCALAR ARGUMENTS logical acneig,sclsys,usefac C All parameters of this routine are entry parameters: C C sclsys: set it equal to TRUE to scale the linear system. C acneig: set it equal to TRUE to stop the factorization if the C matrix of coefficients is not positive definite. C usefac: sset it equal to TRUE if the Cholesky factor is C explicitely needed. end C ****************************************************************** C ****************************************************************** subroutine lssana(nsys,hnnz,hlin,hcol,lssinfo) implicit none C SCALAR ARGUMENTS integer nsys,hnnz,lssinfo C ARRAY ARGUMENTS integer hlin(hnnz),hcol(hnnz) end C ****************************************************************** C ****************************************************************** subroutine lssfac(nsys,hnnz,hlin,hcol,hval,hdiag,d,pind,pval, +nneigv,lssinfo) implicit none C SCALAR ARGUMENTS integer nsys,hnnz,pind,nneigv,lssinfo double precision pval C ARRAY ARGUMENTS integer hlin(hnnz),hcol(hnnz),hdiag(nsys) double precision hval(hnnz),d(nsys) C This routine computes the factorization of a matrix H + D. H is C given in the coordinate format by the arrays hlin, hcol and hval, C all with size hnnz. hdiag(i) stores the position in hval that C holds the i-th diagonal elements of H (if such element is null C and is not present in the coordinate representation, hdiag(i) C should be set to 0). The diagonal matrix D is representend by an C array of nsys elements. C C On return, if the user chose to stop the factorization whenever C the matrix H + D is not positive definite, pind will hold the C pivot index where the factorization failed and pval will hold the C pivot value. nneigv will hold the number of negative eigenvalues C of H + D. end C ****************************************************************** C ****************************************************************** subroutine lsssol(nsys,sol) implicit none C SCALAR ARGUMENTS integer nsys C ARRAY ARGUMENTS double precision sol(nsys) end C ****************************************************************** C ****************************************************************** subroutine lsssoltr(job,nsys,sol) implicit none C SCALAR ARGUMENTS character * 1 job integer nsys C ARRAY ARGUMENTS double precision sol(nsys) C Given the factorization R^T R = H + D, this routine will solve: C R^T x = b, if job = 'T' or 't' and R x = b otherwise. end C ****************************************************************** C ****************************************************************** subroutine lsspermvec(nsys,v) implicit none C SCALAR ARGUMENTS integer nsys C ARRAY ARGUMENTS integer v(nsys) C Permute array v using the same permutation used in the C factorization. end C ****************************************************************** C ****************************************************************** subroutine lssunpermvec(nsys,v) implicit none C SCALAR ARGUMENTS integer nsys C ARRAY ARGUMENTS integer v(nsys) C Permute array v using the inverse permutation used in the C factorization. end C ****************************************************************** C ****************************************************************** subroutine lsspermind(hnnz,hlin,hcol) implicit none C SCALAR ARGUMENTS integer hnnz C ARRAY ARGUMENTS integer hlin(hnnz),hcol(hnnz) C Permute the contents of vectors hlin and hcol using the same C permutation used in the factorization. end C ****************************************************************** C ****************************************************************** subroutine lssunpermind(nsys,hnnz,hlin,hcol) implicit none C SCALAR ARGUMENTS integer nsys,hnnz C ARRAY ARGUMENTS integer hlin(hnnz),hcol(hnnz) C Permute the contents of vectors hlin and hcol using the inverse C permutation used in the factorization. end C ****************************************************************** C ****************************************************************** double precision function lssgetd(j) implicit none C SCALAR ARGUMENTS integer j C Returns the j-th element of the diagonal of factor R (where R is C such that R^T R = H + D). lssgetd = 0.0d0 return end C ****************************************************************** C ****************************************************************** subroutine lsssetrow(nsys) implicit none C SCALAR ARGUMENTS integer nsys end C ****************************************************************** C ****************************************************************** subroutine lssgetrow(nsys,idx,rownnz,rowind,rowval) implicit none C SCALAR ARGUMENTS integer nsys,idx,rownnz C ARRAY ARGUMENTS integer rowind(nsys) double precision rowval(nsys) C Stores in a sparse vector, represented by arrays rowind and C rowval, the idx-th row of factor R (where R is such that R^T R = C H + D). end C ****************************************************************** C ****************************************************************** subroutine lssafsol(nsys,hnnz,hlin,hcol,hval,hdiag,d,sol,lssinfo) implicit none C SCALAR ARGUMENTS integer nsys,hnnz,lssinfo C ARRAY ARGUMENTS integer hlin(hnnz),hcol(hnnz),hdiag(nsys) double precision hval(hnnz),d(nsys),sol(nsys) C Solves a linear system (H + D)x = b. end