sub srs_full_matrix {
    my $mov = shift;
    my $played = shift;
    my $opt = shift || ();
    my $epsilon =  0.001;
    my $maxiter =  1000000;
    my $debug = 0;
    $epsilon = $opt->{epsilon} if ( $opt->{epsilon} );
    $maxiter = $opt->{maxiter} if ( $opt->{maxiter} );
    $debug = $opt->{debug} if ( $opt->{debug} );
    my $srs = $mov->copy();
    my $oldsrs = $srs->copy();
    my $delta = 10.0;
    my $iter = 0;
    while ( $delta > $epsilon and $iter < $maxiter ) {
        my $wt = 1.0 / sumover $played;
        my $prod = $srs x $played;
        my $sos  = $wt * $prod;
        $srs = $mov + $sos;
        $delta = max abs ( $srs - $oldsrs );
        $oldsrs = $srs->copy();
        $iter++;
    }
    print "iter  = $iter\n" if $debug;
    print "epsilon  = $epsilon\n" if $debug;
    printf "delta = %7.4f\n", $delta if $debug;
    my $offset = sum $srs;
    $srs -= ( $offset / $mov->nelem );
    return $srs->slice(":,(0)");
}