how to plot sine and cosine waves in one graph ?

used for academic use

[Walter Roberson]

Please read the guide to tags and retag this question; see http://www.mathworks.co.uk/matlabcentral/answers/43073-a-guide-to-tags

[Manikandan annamalai]

Write a program to plot the function sin(x) between 0≤x≤4π.

[Walter Roberson]

@Manikandan annamalai

Okay, I've done that. Now what?

[Krishan Guiya]

How can I plot cos(ax+b)

[Walter Roberson]

@Krishan Guiya

syms x b
a = randn()

a = -1.0804

f = cos(a*x + b);
fsurf(f, [-10 10 -2*pi 2*pi])
xlabel('x'); ylabel('b')

Answer 1

[Wayne King]

It sounds like the OP wants this in one graph (not subplotted)

     t = 0:0.01:(2*pi);
     x = cos(t);
     y = sin(t);
     plot(t,x,'k'); hold on;
     plot(t,y,'r-.'); 
     axis([0 2*pi -1.5 1.5])
     legend('cos(t)','sin(t)','Location','NorthEast')

[AJAY VISHNU]

thanks

[roger xiang]

thanks

Answer 2

[Sabarinathan Vadivelu]

a = 10;
t = 0 : 0.01 : 10;
A = a*sin(t);
subplot(121),plot(t,A);

B = a*cos(t);
subplot(122),plot(t,B);

[Lee Johnson]

Thanks. What is subplot 121 and 122?

[Stephen23]

@Lee Johnson: syntax not supported by MATLAB. Looks like MatPlotLib to me.

The MATLAB subplot documentation gives this syntax:

 subplot(m,n,p)

and explains what m, n, and p are. There is of course no point in simply copying this info here when you can read in the documentation (see link).

[Walter Roberson]

subplot 121 is archaic, no longer documented, but still works. It is interpreted as subplot(1, 2, 1)

Answer 3

[Ravi Kumar]

x=0:0.1:2*pi;
plot(x,sin(x))
hold on
plot(x,cos(x))

Answer 4

[Abdullah Rajput]

close all; clear all; clc;
t=[0:0.5:180]
x=sind(t);
plot(t,x),hold on
y=cosd(t);
plot(t,y)
legend('Sine wave','Cos wave')

Answer 5

[Konstantin Kuzminov]

hold on not needed

x=0:0.1:2*pi;
plot(x,sin(x),"b",x,cos(x),"g");

"b" and "g" - color

[Walter Roberson]

This is correct.

For old enough MATLAB (before R2017a) replace the "b" by 'b' and "g" by 'g'

[Konstantin Kuzminov]

Walter Roberson, thanks for the clarification about older versions! I did not know that.

[Walter Roberson]

I would not normally have mentioned a backwards compatibility like that now that we are 4 years on, but I suspect this question is getting read by people who are using old versions of MATLAB. (We are getting a rush of people using MATLAB from 2013 and 2015.)

[Konstantin Kuzminov]

You are absolutely right. This is very useful information, because not everyone has the latest versions, they are not required for simple tasks. Correct syntax - 50% success.