## ISINF Test for infinities

Section: Inspection Functions

### Usage

Returns true for entries of an array that are infs (i.e., infinities). The usage is

       y = isinf(x)

The result is a logical array of the same size as `x`, which is true if `x` is not-a-number, and false otherwise. Note that for `complex` or `dcomplex` data types that the result is true if either the real or imaginary parts are infinite.

### Example

Suppose we have an array of floats with one element that is `inf`:

    --> a = [1.2 3.4 inf 5]

    a =

        1.2000    3.4000       inf    5.0000

    --> isinf(a)

    ans =

     0 0 1 0

    --> b = 3./[2 5 0 3 1]

    b =

        1.5000    0.6000       inf    1.0000    3.0000