false — Create logical arrays filled with false values.

false creates logical arrays filled with false values. RunMat mirrors MATLAB sizing semantics across scalar, vector, matrix, and N-D forms.

How false works in RunMat

• false() returns the scalar logical false.
• false(n) returns an n x n logical array of false values.
• false(m, n, ...) returns a logical array with the requested dimensions.
• false(sz) accepts a size vector (row or column) and returns an array with prod(sz) elements arranged using MATLAB column-major ordering.
• false(A) returns a logical array of false with the same size as A.
• false(___, 'like', prototype) uses the prototype only for sizing; the result is still a host logical array.
• false(___, 'logical') is accepted for MATLAB compatibility and has no effect.

Examples

Creating a 2x3 logical array of false values

mask = false(2, 3)

Expected output:

mask = [0 0 0; 0 0 0]

Creating a logical array from a size vector

dims = [1 4 2];
mask = false(dims)

Expected output:

mask =
  1x4x2 logical array
     0     0     0     0
     0     0     0     0

Creating a false mask with the same size as an existing array

A = rand(2, 2);
mask = false(A)

Expected output:

mask =
  2x2 logical array
     0     0
     0     0

FAQ

What does false() return?

It returns the logical scalar false.

Does false(n) create a square array?

Yes. false(n) returns an n x n logical array of false values, matching MATLAB behavior.

How does false(sz) interpret a size vector?

A row or column vector is treated as the full set of dimensions, so false([2 3 4]) yields a 2x3x4 logical array.

Does false keep results on the GPU?

No. The builtin always returns a host logical array. gpuArray inputs are only used to infer the output size.

Is the 'logical' option required?

No. false always returns logical values; the 'logical' option is accepted only for MATLAB compatibility.

Related functions to explore

These functions work well alongside false. Each page has runnable examples you can try in the browser.

true, logical, islogical, zeros, colon, eye, fill, linspace, logspace, magic, meshgrid, ones, rand, randi, randn, randperm, range

Open-source implementation

Unlike proprietary runtimes, every RunMat function is open-source. Read exactly how false works, line by line, in Rust.

• View false.rs on GitHub
• Learn how the runtime works
• Found a bug? Open an issue with a minimal reproduction.

About RunMat

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• Simulations that took hours now take minutes. RunMat automatically optimizes your math for GPU execution on Apple, Nvidia, and AMD hardware. No code changes needed.
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