Plotting over a certain range, what am i doing wrong here?

I am looking to plot this sinusoidal curve over just a desired range, from theta=120 to theta=150 here

It must be zero before 120 and after 150

The code is as written below,

x = 0:0.1:3.14;
y = sin(x);
theta = 0:360;
if theta(theta(1,:)<120) && theta(theta(1,:)>150)
    yy = 0;
else
    yy = y;
end
plot(theta,yy)

Its returning me errors saying,

Operands to the || and && operators must be convertible to logical scalar values.

How do i approach this problem?

Answer 1

[Star Strider]

Mixing radian and degree angle units makes this a bit more challenging.

Try this:

yfcn = @(a) sin(a) .* ((120*pi/180 < a) & (150*pi/180 > a));
x = 0:0.1:pi;

figure
plot(x, yfcn(x))
grid

Note that in your original code, ‘theta’ and ‘x’ are vastly different sizes, so the plot would never work regardless. Beyond that, to compare vector elements, use single logical operators, not double logical operators.

.

[Sandip Ghatge]

This completely worked, thank you very much

Just a small doubt,

What is a here? and how is yfcn is not in terms of 'x' and still plotting values from 'x'

[Star Strider]

My pleasure.

I created ‘yfcn’ as an anonymous function, and ‘a’ is the argument to it. Anonymous functions are similar to other functions, and can be called the same way. See the documentation on Anonymous Functions for a full discussion.

.

[Sandip Ghatge]

Thanks for the explanation:)

[Star Strider]

As always, my pleasure!