# isinf

Determine which array elements are infinite

## Syntax

``TF = isinf(A)``

## Description

example

````TF = isinf(A)` returns a logical array containing `1` (`true`) where the elements of the array `A` are `Inf` or `-Inf`, and `0` (`false`) where they are not. If `A` contains complex numbers, `isinf(A)` contains `1` for elements with infinite real or imaginary part, and `0` for elements where both real and imaginary parts are finite or `NaN`.```

## Examples

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Create a row vector and determine the infinite elements.

`A = 1./[-2 -1 0 1 2]`
```A = 1×5 -0.5000 -1.0000 Inf 1.0000 0.5000 ```
`TF = isinf(A)`
```TF = 1x5 logical array 0 0 1 0 0 ```

Create an array of complex numbers. Determine whether the complex numbers contain infinite values.

`A = [2 + 1i, 3 + 1i/0, 0/0 - 2i]`
```A = 1×3 complex 2.0000 + 1.0000i 3.0000 + Infi NaN - 2.0000i ```
`TF = isinf(A)`
```TF = 1x3 logical array 0 1 0 ```

The second element of `A` has an infinite imaginary part. For this element, `isinf` returns 1.

## Input Arguments

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Input array, specified as a scalar, vector, matrix, or multidimensional array.

## Tips

• If `x` is a real scalar, exactly one of `isfinite(x)`, `isinf(x)`, and `isnan(x)` returns logical `1` (`true`).

• For a complex scalar `z`, `isinf(z)` and `isnan(z)` can both return logical 1. For example, `isinf(complex(Inf,NaN))` and `isnan(complex(Inf,NaN))` both return logical 1.