# real

Real part of complex number

## Syntax

``real(z)``

## Description

example

````real(z)` returns the real part of `z`. If `z` is a matrix, `real` acts elementwise on `z`.```

## Examples

### Compute Real Part of Numeric Inputs

Find the real parts of these numbers. Because these numbers are not symbolic objects, you get floating-point results.

`[real(2 + 3/2*i), real(sin(5*i)), real(2*exp(1 + i))]`
```ans = 2.0000 0 2.9374```

### Compute Real Part of Symbolic Inputs

Compute the real parts of the numbers converted to symbolic objects:

`[real(sym(2) + 3/2*i), real(4/(sym(1) + 3*i)), real(sin(sym(5)*i))]`
```ans = [ 2, 2/5, 0]```

Compute the real part of this symbolic expression:

`real(2*exp(1 + sym(i)))`
```ans = 2*cos(1)*exp(1)```

### Compute Real Part of Symbolic Expressions

In general, `real` cannot extract the entire real parts from symbolic expressions containing variables. However, `real` can rewrite and sometimes simplify the input expression:

```syms a x y real(a + 2) real(x + y*i)```
```ans = real(a) + 2 ans = real(x) - imag(y)```

If you assign numeric values to these variables or specify that these variables are real, `real` can extract the real part of the expression:

```syms a a = 5 + 3*i; real(a + 2)```
```ans = 7```
```syms x y real real(x + y*i)```
```ans = x```

Clear the assumption that `x` and `y` are real by recreating them using `syms`:

`syms x y`

### Compute Real Part for Matrix Input

Find the real parts of the elements of matrix `A`:

```syms x A = [-1 + sym(i), sinh(x); exp(10 + sym(7)*i), exp(sym(pi)*i)]; real(A)```
```ans = [ -1, real(sinh(x))] [ cos(7)*exp(10), -1]```

## Input Arguments

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Input, specified as a number, vector, matrix, or array, or a symbolic number, variable, array, function, or expression.

## Tips

• Calling `real` for a number that is not a symbolic object invokes the MATLAB® `real` function.

## Alternatives

You can compute the real part of `z` via the conjugate: `real(z)= (z + conj(z))/2`.