# realmax

Largest positive floating-point number

## Syntax

``f = realmax``
``f = realmax(precision)``
``f = realmax("like",p)``

## Description

example

````f = realmax` returns the largest finite floating-point number in IEEE® double precision. This is equal to `(2-2^(-52))*2^1023`.```

example

````f = realmax(precision)` returns the largest finite floating-point number in IEEE single or double precision. This is equal to `realmax` for double precision, and to `single((2-2^(-23))*2^127)` for single precision.```

example

````f = realmax("like",p)` returns the largest finite floating-point number with the same data type, sparsity, and complexity (real or complex) as the floating-point variable `p`.```

## Examples

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Set the output format to long scientific notation. Return the largest finite floating-point number in IEEE® double precision.

```format long e f = realmax```
```f = 1.797693134862316e+308 ```

Return the largest finite floating-point number in IEEE® single precision.

`f = realmax("single")`
```f = single 3.4028e+38 ```

Check the class of `f`.

`class(f)`
```ans = 'single' ```

Return the largest finite floating-point number with the same data type and complexity as an existing array.

First, create a complex vector of `single` data type.

`p = single([0.12+2i -0.5i 3]);`

Return the largest finite floating-point number as a scalar that is complex like `p.`

`f = realmax("like",p)`
```f = single 3.4028e+38 +0.0000e+00i ```

Create a 10-by-10 sparse matrix.

`p = sparse(10,10,pi);`

Return the largest finite floating-point number with the same data type and sparsity as `p`. The output is a 1-by-1 sparse matrix.

`f = realmax("like",p)`
```f = (1,1) 1.7977e+308 ```

## Input Arguments

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Floating-point precision type, specified as `"double"` or `"single"`.

Prototype, specified as a floating-point variable.

Data Types: `double` | `single`
Complex Number Support: Yes

## Version History

Introduced before R2006a