docs: public boolean process( int sideLength,
                              double diag[] ,
                              double off[] ,
                              double eigenvalues[] ) {
          if( diag != null )
              helper.init(diag,off,sideLength);
          if( Q == null )
              Q = CommonOps_DDRM.identity(helper.N);
          helper.setQ(Q);
  
          this.followingScript = true;
          this.eigenvalues = eigenvalues;
          this.fastEigenvalues = false;
  
          return _process();
      }