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Convert to 8-bit signed integer


intArray = int8(array)


intArray = int8(array) converts the elements of an array into signed 8-bit (1-byte) integers of class int8.

Input Arguments


Array of any numeric class, such as single or double. If array is already of class int8, the int8 function has no effect.

Output Arguments


Array of class int8. Values range from –27 to 27 – 1.

The int8 function maps any values in array that are outside the limit to the nearest endpoint. For example,

int8(2^7)   % 2^7 = 128


ans =


Convert a double array to int8:

mydata = int8(magic(10));


When preallocating integer arrays, specify the class in the call to functions that support a class name input (such as zeros, ones or eye), rather than calling an integer conversion function. For example,

I = int8(zeros(100));     % Creates an intermediate array

is not as efficient as

I = zeros(100, 'int8');   % Preferred 

Extended Capabilities

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

Introduced before R2006a

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