MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi

# How do I plot a function that consists of a variable depending on x?

Asked by Flávio on 5 Jan 2013

For example, after some calculations to solve my problem, I get y=x^3.

How do I plot that function? I tried to do fplot(@(x) y, limits) but it doesn't work...any solution?

## Products

No products are associated with this question.

Answer by Walter Roberson on 5 Jan 2013
```ezplot('x^3', limits)
```

OR

```ezplot(@(x) x.^3, limits)
```

OR

```x = linspace(LowerLimit, UpperLimit, NumberofPoints);
plot(x, x.^3)
```

Or more generally if you have a symbolic variable y that contains the expression,

```f = matlabFunction(y, 'x');
```

and then

```ezplot(f, limits)
```

or

```x = linspace(LowerLimit, UpperLimit, NumberofPoints);
plot(x, f(x))
```

Flávio on 5 Jan 2013

Thank you man! It was the matlabFunction that I needed!

Walter Roberson on 5 Jan 2013

Answer by Jing on 5 Jan 2013
Edited by Jing on 5 Jan 2013

Hi, It should be like this:

```y=@(x) x^3; fplot(y,[-10,10]);
or
fplot(@(x) x^3,[-10,10])
```

You need to define the function handle.

## 1 Comment

Flávio on 5 Jan 2013

Thank you;)