User`s manual

3 Creating Fortran MEX-Files

3-30

C Get the size and pointers to input data.

m = mxGetM(prhs(1))

n = mxGetN(prhs(1))

pr = mxGetPr(prhs(1))

C Allocate space.

C NOTE: Assume at most 20% of the data is sparse.

nzmax = dble(m*n) *.20 + .5

C NOTE: The maximum number of non-zero elements cannot be less

C than the number of columns in the matrix.

if (n .gt. nzmax) then

nzmax = n

endif

plhs(1) = mxCreateSparse(m,n,nzmax,0)

sr = mxGetPr(plhs(1))

irs = mxGetIr(plhs(1))

jcs = mxGetJc(plhs(1))

C Load the sparse data.

if (loadsparse(%val(pr),%val(sr),%val(irs),%val(jcs),

+m,n,nzmax) .eq. 1) then

call mexPrintf('Truncating output, input is > 20%% sparse')

endif

return

end

This is the subroutine that fulltosparse calls to fill the mxArray with the

sparse data.

C $Revision: 1.4 $

C===============================================================

C loadsparse.f

C This is the subfunction called by fulltosparse that fills the

C mxArray with the sparse data. Your version of

C loadsparse can operate however you would like it to on the

C data.