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Absolute value and complex magnitude



Y = abs(X) returns the absolute value of each element in array X.

If X is complex, abs(X) returns the complex magnitude.


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y = abs(-5)
y = 5

Create a numeric vector of real values.

x = [1.3 -3.56 8.23 -5 -0.01]'
x = 5×1


Find the absolute value of the elements of the vector.

y = abs(x)
y = 5×1


y = abs(3+4i)
y = 5

Input Arguments

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Input array, specified as a scalar, vector, matrix, or multidimensional array. If X is complex, then it must be a single or double array. The size and data type of the output array is the same as the input array.

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

More About

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Absolute Value

The absolute value (or modulus) of a real number is the corresponding nonnegative value that disregards the sign.

For a real value, a, the absolute value is:

  • a, if a is greater than or equal to zero

  • -a, if a is less than zero

abs(-0) returns 0.

Complex Magnitude

The complex magnitude (or modulus) is the length of a vector from the origin to a complex value plotted in the complex plane.

For a complex value, |a+bi| is defined as a2+b2.

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

See Also

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