参考网址：https://ww2.mathworks.cn/help/matlab/creating_plots/greek-letters-and-special-characters-in-graph-text.html?searchHighlight=latex&s_tid=srchtitle
for example:
x=linspace(0,2*pi);plot(x,sin(x));title('x~{chi}_{alpha}^{2}(3)');xlabel('(t_{2}^{2}-t_{4}^{2})/t_{4}^{2}');
figure is that:
