【转自：http://blog.****.net/fendoubasaonian/article/details/52974608】
%JOINT Summary of this function goes here
% Detailed explanation goes here
t1 = linspace(-10,10,500);
t2 = linspace(-10,10,500);
t3 = linspace(-10,10,500);
% zhx = -12.1*sin(2*pi*(time-0.25))-abs(12.1*sin(2*pi*(time-0.25)));
% zhx = 0;
a = 1;
c = 0;
% sigmod & tanh
sigmod = sigmf(t1,[a c])
tan_h = tanh(t2);
max_f = max(0,t3);
%激活函数
subplot(2,2,1);
plot(t1, sigmod,\'r-\');
legend(\'sigmoid\')
title(\'sigmoid函数\')
axis([-10, 10, -1, 1]) % 坐标轴的显示范围
set(gca, \'XGrid\',\'on\'); % X轴的网格
set(gca, \'YGrid\',\'on\'); % Y轴的网格
subplot(2,2,2);
plot(t2,tan_h,\'b-\');
legend(\'tanh\')
title(\'tanh函数\')
axis([-10, 10, -1, 1]) % 坐标轴的显示范围
set(gca, \'XGrid\',\'on\'); % X轴的网格
set(gca, \'YGrid\',\'on\'); % Y轴的网格
subplot(2,2,3);
plot(t3,max_f,\'c-\');
legend(\'max(0,x)\')
title(\'max(0,x)函数\')
axis([-10, 10, -10, 10]) % 坐标轴的显示范围
set(gca, \'XGrid\',\'on\'); % X轴的网格
set(gca, \'YGrid\',\'on\'); % Y轴的网格