MATLAB: Plot range -pi to pi

range of pitrig functions

how we can plot sine, cosine and tangent on one Figure window ,my problem was the range –> -π < θ < π.

Best Answer

Try this:
% Initialization / clean-up code.
clc; % Clear the command window.
close all; % Close all figures (except those of imtool.)
clear; % Erase all existing variables. Or clearvars if you want.
workspace; % Make sure the workspace panel is showing.
format long g;
format compact;
fontSize = 20;
theta = linspace(-pi, pi, 1000);
period = 3*pi/4; % Whatever you want.
sint = sin(2 * pi * theta / period);
plot(theta, sint, 'b-', 'LineWidth', 2);
hold on;
cosinet = cos(2 * pi * theta / period);
plot(theta, cosinet, 'r-', 'LineWidth', 2);
tant = tan(2 * pi * theta / period);
plot(theta, tant, '-', 'Color', [0, 0.5, 0], 'LineWidth', 2);
grid on;
xlabel('Theta [in radians]', 'FontSize', fontSize);
ylabel('Amplitude (signal value)', 'FontSize', fontSize);
title('Trig functions versus Theta', 'FontSize', fontSize);
legend('Sine', 'Cosine', 'Tangent');
% The tangent spikes are so big that we can't see the sin and cosine.
% Let's limit the y range to +/- 4;
ylim([-4, 4]);
% Set up figure properties:
% Enlarge figure to full screen.
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);
% Get rid of tool bar and pulldown menus that are along top of figure.
set(gcf, 'Toolbar', 'none', 'Menu', 'none');
% Give a name to the title bar.
set(gcf, 'Name', 'Demo by ImageAnalyst', 'NumberTitle', 'Off')