@Override
    public void solve( DenseMatrix64F B , DenseMatrix64F X ) {
        if( B.numCols != X.numCols || B.numRows != n || X.numRows != n) {
            throw new IllegalArgumentException("Unexpected matrix size");
        }

        int numCols = B.numCols;

        double dataB[] = B.data;
        double dataX[] = X.data;

        if(decomp.isLower()) {
            for( int j = 0; j < numCols; j++ ) {
                for( int i = 0; i < n; i++ ) vv[i] = dataB[i*numCols+j];
                solveInternalL();
                for( int i = 0; i < n; i++ ) dataX[i*numCols+j] = vv[i];
            }
        } else {
            throw new RuntimeException("Implement");
        }
    }