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nextpow2

Next power of two

Syntax

Description

p = nextpow2(A) returns the smallest power of two that is greater than or equal to the absolute value of A. (That is, p that satisfies 2^p >= abs(A)).

This function is useful for optimizing FFT operations, which are most efficient when sequence length is an exact power of two.

If A is non-scalar, nextpow2 returns the smallest power of two greater than or equal to length(A).

Examples

For any integer n in the range from 513 to 1024, nextpow2(n) is 10.

For a 1-by-30 vector A, length(A) is 30 and nextpow2(A) is 5.

See Also

fft, log2, pow2


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