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8-bit unsigned integer arrays


Variables in MATLAB® of data type (class) uint8 are stored as 1-byte (8-bit) unsigned integers. For example:

y = uint8(10);
whos y
  Name      Size            Bytes  Class    Attributes

  y         1x1                 1  uint8                  

For more information on integer types, see Integers.


Some array creation functions allow you to specify the data type. For instance, zeros(100,'uint8') creates a 100-by-100 matrix of zeros of type uint8.

If you have an array of a different type, such as double or single, then you can convert that array to an array of type uint8 by using the uint8 function.


Y = uint8(X)



Y = uint8(X) converts the values in X to type uint8. Values outside the range [0,28-1] map to the nearest endpoint.

Input Arguments

expand all

Input array, specified as a scalar, vector, matrix, or multidimensional array.

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


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Convert a double-precision variable to an 8-bit unsigned integer.

x = 100;
xtype = class(x)
xtype = 
y = uint8(x)
y = uint8

Extended Capabilities

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

Introduced before R2006a

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