UFgetPetscMat
Date: 2016-07-24

    % UFgetPetscMat.m
       petsc-3.7.3 2016-07-24
       Report Typos and Errors
    % modified from UFget_example.m
    %   This script
    %     (1) gets the selected index file of the UF sparse matrix collection,
    %     (2) loads in matrices in matlab format in increasing order of
    %         number of rows in the selected matrices,
    %     (3) writes into PETSc binary format in the given directory with
    %         each matrix named as A_{id}
    %
    %   See also UFget_example.m
    %   Copyright 2009, PETSc Team.

    index = UFget;

    % sets selection here
    f = find (index.nrows == index.ncols & index.nrows > 940000 & index.isReal) ;
    [y, j] = sort (index.nrows (f)) ;
    f = f (j) ;

    for i = f
        %loads in matrix in matlab format
        %---------------------------------
        fprintf ('Loading %s%s%s, please wait ...\n', ...
            index.Group {i}, filesep, index.Name {i}) ;
        Problem = UFget (i,index) ;
        disp (Problem) ;
        title (sprintf ('%s:%s', Problem.name, Problem.title')) ;

        % convets to PETSc binary format and writes into ~mat/A_{id}
        %-----------------------------------------------------------
        fname = ['mat/A',num2str(i)];
        fprintf ('write matrix into petsc binary file %s ...\n',fname);
        PetscBinaryWrite(fname,Problem.A);
        %input ('hit enter to continue:') ;
    end