realmax - Largest positive floating-point number - MATLAB (original) (raw)

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Largest positive floating-point number

Syntax

Description

[f](#mw%5F56ff5a35-e70e-47e8-b47c-9720eff39805) = realmax returns the largest finite floating-point number in IEEE® double precision. This is equal to(2-2^(-52))*2^1023.

example

[f](#mw%5F56ff5a35-e70e-47e8-b47c-9720eff39805) = realmax([precision](#mw%5Ff86e82a6-15c0-4d28-8a79-a46160e342dc)) 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](#mw%5F56ff5a35-e70e-47e8-b47c-9720eff39805) = realmax(like=[p](#mw%5Fa3465443-498e-472a-b534-a0c4b72783c6)) returns the largest finite floating-point number with the same data type, sparsity, and complexity (real or complex) as the floating-point variable p.

example

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.

Check the class of f.

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 = single

3.4028e+38 +0.0000e+00i

Create a 10-by-10 sparse matrix.

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 = sparse double (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

Output Arguments

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Largest floating-point number, returned as a scalar.

Extended Capabilities

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This function supports tall arrays with the limitations:

• The supported syntax is realmax(like=p), where the underlying data type of p must be a floating-point type.

For more information, see Tall Arrays.

The realmax function supports GPU array input with these usage notes and limitations:

• The supported syntax is realmax(like=p), where the underlying data type of p must be a floating-point type.

For more information, see Run MATLAB Functions on a GPU (Parallel Computing Toolbox).

Usage notes and limitations:

• The supported syntax is realmax(like=p), where the underlying data type of p must be a floating-point type.

For more information, see Run MATLAB Functions with Distributed Arrays (Parallel Computing Toolbox).

Version History

Introduced before R2006a