Inf - Create array of all Inf values - MATLAB (original) (raw)

Create array of all Inf values

Syntax

Description

[X](#mw%5F4aaa8a5a-52ab-4405-b990-8109114167b1) = Inf returns the scalar representation of positive infinity. Operations return Inf when their result is too large to represent as a floating point number, such as1/0 or log(0).

For double-precision, Inf represents numbers larger thanrealmax. For single-precision, Inf represents numbers larger than realmax("single").

[X](#mw%5F4aaa8a5a-52ab-4405-b990-8109114167b1) = Inf([n](#mw%5F2f12dbe2-ef8f-43b8-a08e-ffb69474a663)) returns an n-by-n matrix ofInf values.

example

[X](#mw%5F4aaa8a5a-52ab-4405-b990-8109114167b1) = Inf([sz1,...,szN](#mw%5Ffc869e12-a06c-400e-b788-b592b610b4b1)) returns an sz1-by-...-by-szN array ofInf values, where sz1,...,szN indicate the size of each dimension. For example, Inf(3,4) returns a 3-by-4 matrix.

example

[X](#mw%5F4aaa8a5a-52ab-4405-b990-8109114167b1) = Inf([sz](#mw%5F24dbe3ac-d584-4729-98ab-a44f5bcef97e)) returns an array of Inf values, where the size vectorsz defines size(X). For example,Inf([3 4]) returns a 3-by-4 matrix.

example

[X](#mw%5F4aaa8a5a-52ab-4405-b990-8109114167b1) = Inf(___,[typename](#mw%5Fc9b67466-41e9-438d-9597-b3f1f90d0b59)) returns an array of Inf values of data typetypename, which can be either "single" or "double".

example

[X](#mw%5F4aaa8a5a-52ab-4405-b990-8109114167b1) = Inf(___,like=[p](#mw%5Fda3f762c-cf6c-44b8-9faa-d55b8dd8b04f)) returns an array of Inf values of the same data type, sparsity, and complexity (real or complex) as p. You can specify typename or like but not both.

example

Examples

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Create a 3-by-3 matrix of Inf values.

X = 3×3

Inf Inf Inf Inf Inf Inf Inf Inf Inf

Create a 2-by-3-by-4 array of Inf values and display its size.

Create an array of Inf values that is the same size as an existing array.

A = [1 4; 2 5; 3 6]; sz = size(A); X = Inf(sz)

X = 3×2

Inf Inf Inf Inf Inf Inf

It is a common pattern to combine the previous two lines of code into a single line.

Create a 1-by-3 vector of Inf values whose elements are of type single.

X = 1×3 single row vector

Inf Inf Inf

You can also specify the output type based on the type of another variable. Create a variable p of type single. Then, create a vector of Inf values with the same size and type as p.

p = single([1 2 3]); X = Inf(size(p),like=p)

X = 1×3 single row vector

Inf Inf Inf

Input Arguments

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Size of square matrix, specified as an integer.

• If n is 0, then X is an empty matrix.
• If n is negative, then it is treated as 0.

Data Types: double | single | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64

Size of each dimension in a list, specified as separate integer arguments.

• If the size of any dimension is 0, then X is an empty array.
• If the size of any dimension is negative, then it is treated as 0.
• Beyond the second dimension, Inf ignores trailing dimensions of length 1. For example,Inf(3,1,1) creates a 3-by-1 vector ofInf values.

Data Types: double | single | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64

Size of each dimension in a vector, specified as a row vector of integers.

• If the size of any dimension is 0, then X is an empty array.
• If the size of any dimension is negative, then it is treated as 0.
• Beyond the second dimension, Inf ignores trailing dimensions of length 1. For example, Inf([3 1]) creates a 3-by-1 vector ofInf values.

Data Types: double | single | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64

Data type to create, specified as "double" or"single".

Prototype of array to create, specified as an array.

Data Types: double | single
Complex Number Support: Yes

Output Arguments

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Array of Inf values, returned as a scalar, vector, matrix, or multidimensional array.

Extended Capabilities

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Usage notes and limitations:

• Dimensions must be real, nonnegative, integers.

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

• You can specify typename as 'gpuArray'. If you specifytypename as 'gpuArray', the default underlying type of the array is double.
  To create a GPU array with underlying type datatype, specify the underlying type as an additional argument beforetypename. For example, X = Inf(3,datatype,'gpuArray') creates a 3-by-3 GPU array of allInf values with underlying typedatatype.
  You can specify the underlying type datatype as one of these options:
  • 'double'
  • 'single'
• You can also specify the numeric variable p as agpuArray.
  If you specify p as a gpuArray, the underlying type of the returned array is the same as p.

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

Usage notes and limitations:

• You can specify typename as 'codistributed' or'distributed'. If you specify typename as'codistributed' or 'distributed', the default underlying type of the returned array is double.
  To create a distributed or codistributed array with underlying typedatatype, specify the underlying type as an additional argument before typename. For example,X = Inf(3,datatype,'distributed') creates a 3-by-3 distributed array of all Inf values with underlying typedatatype.
  You can specify the underlying type datatype as one of these options:
  • 'double'
  • 'single'
• You can also specify p as a codistributed or distributed array.
  If you specify p as a codistributed ordistributed array, the underlying type of the returned array is the same as p.
• For additional codistributed syntaxes, see Inf (codistributed) (Parallel Computing Toolbox).

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

Version History

Introduced before R2006a