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subroutine dspms(nra,nca,ncb,a,nela,inda,b,mrb,c,mrc)
c**********************************************************
c multiply sparse matrix stored in a,inda on right by full
c matrix stored in b. put result in c.
c*** input
c nra actual row dimension of a and c matrix
c nca actual column dimension of a and row dimension of b matrix
c ncb actual column dimension of a and c matrices
c a a one-dimensional array containing the non-zero elements
c of the first matrix,arranged row-wise, but not
c necessarily in order within rows.
c nela number of non-zero elements in a
c inda(i) 1<=i<=nra number of non-zero elements in row i of a.
c inda(nra+i) 1<=i<nela column index of i'th non-zero element of a.
c b a two-dimensional array containing all the
c elements of the second matrix.
c mrb row-dimension of b in calling routine.
c mrc row-dimension of c in calling routine.
c*** output
c c a two-dimensional array containing all the
c elements of the product matrix.
c!
c Copyright INRIA
double precision a(*), b(mrb,ncb), c(mrc,ncb)
integer inda(*)
double precision t
c
c nrc,ncc are number of rows,columns in c.
nrc = nra
ncc = ncb
c clear c to zero.
10 do 30 i=1,nrc
do 20 j=1,ncc
c(i,j) = 0.0d0
20 continue
30 continue
c n2 will be pointer to end of row i of a.
n2 = 0
c i will be row-index for a.
do 60 i=1,nra
c pick out number of non-zero elements in row i.
nir = inda(i)
c if no non-zeroes skip processing of row i of a.
if (nir.eq.0) go to 60
c n1 points to start of row i in a,n2 to end.
n1 = n2 + 1
n2 = n2 + nir
c process row i of a, i.e. form all products of non-zero a(i,l) with
c b(l,j); put into c(i,j).
c k points to non-zero elements in row i of a.
do 50 k=n1,n2
l = inda(nra+k)
t = a(k)
do 40 j=1,ncb
c(i,j) = c(i,j) + t*b(l,j)
40 continue
50 continue
60 continue
return
end
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