#!/usr/bin/env ruby require("gsl") m = NMatrix[[1.0, 1/2.0, 1/3.0, 1/4.0], [1/2.0, 1/3.0, 1/4.0, 1/5.0], [1/3.0, 1/4.0, 1/5.0, 1/6.0], [1/4.0, 1/5.0, 1/6.0, 1/7.0]] p GSL::Eigen.symm(m) p GSL::Eigen.symmv(m)