`nextpow2` — Return next-power-of-two exponents in MATLAB and RunMat.

nextpow2(X) returns exponent values p such that 2^p is the next power of two greater than or equal to abs(X). Element-wise mapping and zero handling follow MATLAB semantics.

Syntax

p = nextpow2(X)

Inputs

Name	Type	Required	Default	Description
`X`	`Any`	Yes	—	Real numeric/logical input.

Returns

Name	Type	Description
`p`	`NumericArray`	Exponent p where 2^p >= abs(X).

Errors

Identifier	When	Message
`RunMat:nextpow2:InvalidInput`	Input is not convertible to a supported real numeric tensor.	`nextpow2: invalid input`
`RunMat:nextpow2:Internal`	Internal gather/provider/tensor construction failed.	`nextpow2: internal error`

How `nextpow2` works

nextpow2 accepts real numeric scalars and tensors.
The transform is applied elementwise for array inputs.
Zero maps to 0.
Negative values use abs(X) before computing the exponent.
Inf remains infinite and NaN remains NaN.
GPU tensors use a unary provider hook when available and otherwise gather to the host.
The output preserves the input's scalar/tensor shape.

Examples

Compute an FFT-friendly zero-padding length

x = rand(1000, 1);
N = 2^nextpow2(length(x))

Apply nextpow2 elementwise to an array

p = nextpow2([0 1 3 9])

Expected output:

p = [0 0 2 4]

Using `nextpow2` with coding agents

Open a RunMat example with live inputs, then ask the agent to explain how nextpow2 changes the result.

Run a small nextpow2 example, explain the result, then change one input and compare the output.

FAQ

Why does nextpow2 return an exponent instead of the actual power of two?⌄

That matches MATLAB semantics. To get the actual power of two, use 2^nextpow2(x) for a scalar or 2.^nextpow2(X) elementwise for arrays.

How is nextpow2 used in FFT workflows?⌄

A common pattern is N = 2^nextpow2(length(x)), which computes a power-of-two transform length suitable for zero padding before an FFT.

Does nextpow2 preserve array shape?⌄

Yes. The transform is elementwise and the output has the same scalar/tensor shape as the input.

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nextpow2 — Return next-power-of-two exponents in MATLAB and RunMat.

Syntax

Inputs

Returns

Errors

How nextpow2 works

Examples

Compute an FFT-friendly zero-padding length

Apply nextpow2 elementwise to an array

Using nextpow2 with coding agents

FAQ

Related Math functions

Elementwise

Trigonometry

Reduction

Structure

Signal

Rounding

Factor

Solve

Optim

Ops

Symbolic

Fft

Interpolation

Discrete

Ode

Poly

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`nextpow2` — Return next-power-of-two exponents in MATLAB and RunMat.

How `nextpow2` works

Using `nextpow2` with coding agents