iscolumn — Return true when an array has exactly one column.

iscolumn(A) returns true when the second MATLAB-visible dimension of A is one.

Syntax

tf = iscolumn(A)

Inputs

NameTypeRequiredDefaultDescription
AAnyYesInput value to inspect.

Returns

NameTypeDescription
tfLogicalArrayTrue when input has one column.

How iscolumn works

  • Scalars and N-by-1 arrays return true.
  • 1-by-N arrays with N other than one return false.
  • The predicate uses the same dimension metadata as size.

Does RunMat run iscolumn on the GPU?

No GPU kernels are launched.

GPU memory and residency

The result is a host logical scalar.

Example

Testing row and column vectors

iscolumn([1 2 3])
iscolumn([1; 2; 3])

Expected output:

ans = logical(0)
ans = logical(1)

Using iscolumn with coding agents

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

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

FAQ

Is a scalar a column?

Yes. A scalar is 1-by-1.

Introspection

isempty · ismatrix · isrow · isscalar · isvector · length · ndims · numel · size

Shape

blkdiag · cat · circshift · diag · flip · fliplr · flipud · horzcat · ipermute · kron · permute · repelem · repmat · reshape · rot90 · squeeze · toeplitz · tril · triu · vertcat

Creation

colon · eye · false · fill · full · inf · linspace · logspace · magic · meshgrid · nan · nchoosek · ndgrid · nonzeros · ones · peaks · perms · rand · randi · randn · randperm · range · sparse · spdiags · speye · spones · sprand · true · zeros

Indexing

find · ind2sub · sub2ind

Open-source implementation

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

About RunMat

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