%macro mult_matrix(in1=, in2=, out1=);

    %do i = 1 %to 2;
        proc contents data = &&in&i.. out = __m&i.(keep=name varnum nobs) noprint;
        run;

        * 変数名・行数・列数をマクロ変数に格納 ;
        data _null_;
            set __m&i. end = eof;
            call symputx("x&i._" || compress(put(_n_, best.)), name);
            if eof then do;
                call symputx("r&i.", nobs);
                call symputx("c&i.", varnum);
            end;
        run;

        * 変数名を変換 ;
        data _m&i.;
            set &&in&i..;
            rename %do j = 1 %to &&c&i..;
                       &&x&i._&j.. = x&i._&j.
                   %end;
            ;
        run;
    %end;

    * 行列の積を計算 ;
    proc ds2;
        data &out1. / overwrite = yes;
            drop i x:;
            declare double i;
            vararray double x1_[&c1.];
            vararray double x2_[&c2.];
            vararray double z[&c2.];

            declare package matrix m1 m2 m3;

            method init();
                m1 = _new_ [this] matrix(&r1., &c1.);
                m2 = _new_ [this] matrix(&r2., &c2.);

                do i = 1 to &r1.;
                    set _m1;
                    m1.in(x1_, i);
                end;

                do i = 1 to &r2.;
                    set _m2;
                    m2.in(x2_, i);
                end;
            end;

            method term();
                m3 = m1.mult(m2);

                do i = 1 to &r1.;
                    m3.out(z, i);
                    output;
                end;
            end;
        enddata;
        run;
    quit;

%mend mult_matrix;