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isinteger

Determine whether input is integer array

Description

example

TF = isinteger(A) returns logical 1 (true) if A is an array of integer type. Otherwise, it returns logical 0 (false).

Integer types in MATLAB® include: int8, int16, int32, int64, uint8, uint16, uint32, and uint64. For more information, see Integer Classes.

Examples

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Determine if a real number is an integer type.

TF = isinteger(2)
TF = logical
   0

MATLAB® stores a real number as a double type by default.

Convert the number to a signed 8-bit integer type using the int8 function. Check if it is an integer type.

TF = isinteger(int8(2))
TF = logical
   1

Determine if a complex number is an integer type.

A = 3.5 - 2.5i
A = 3.5000 - 2.5000i
TF = isinteger(A)
TF = logical
   0

MATLAB stores a complex number as a double type by default.

Convert the complex number into a signed 32-bit integer type using the int32 function. Check if it is an integer type.

B = int32(A)
B = int32
    4 -    3i
TF = isinteger(B)
TF = logical
   1

When a number with decimal digits is converted to an integer type, MATLAB rounds it to the nearest integer.

Determine if an array containing integer numbers is an integer type.

Create an array using the int8 function. Check if it is an integer type.

A = [int8(1:5)]
A = 1x5 int8 row vector

   1   2   3   4   5

TF = isinteger(A)
TF = logical
   1

Now, create a cell array that contains the array A and other integer numbers. Use class to identify the type of the cell array. Check if it is an integer type.

B = {A int8(-4); int8(2) int8(1)}
B=2×2 cell array
    {[1 2 3 4 5]}    {[-4]}
    {[        2]}    {[ 1]}

type = class(B)
type = 
'cell'
TF = isinteger(B)
TF = logical
   0

The cell array is not an integer type since it is a cell type.

Input Arguments

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Input array, specified as a scalar, vector, matrix, or multidimensional array. MATLAB has the following integer types.

Integer TypeDescription

int8

8-bit signed integer

int16

16-bit signed integer

int64

64-bit signed integer

int32

32-bit signed integer

uint8

8-bit unsigned integer

uint16

16-bit unsigned integer

uint32

32-bit unsigned integer

uint64

64-bit unsigned integer

Tips

  • For a floating-point number of a single or double type, you can check if it is also an integer by using the round function (within the floating-point relative accuracy eps). If the rounded value of the number is equal to the original value before rounding, then the number is an integer. For example, 2 == round(2) returns logical 1 (true) since 2 is an integer.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using MATLAB® Coder™.

GPU Code Generation
Generate CUDA® code for NVIDIA® GPUs using GPU Coder™.

Version History

Introduced before R2006a