iscolumn check if a variable is a column

## Syntax

    t=iscolumn(x)

## Arguments

x

  scalar,vector, matrix, hypermatrix, list, array of structures or cells

t

  a boolean

## Description

`iscolumn(`x`)` returns true if `x` is a column vector. Scalars are considered as columns.

Note that `iscolumn([])` returns false.

## Examples

    iscolumn(ones(10,1))
    iscolumn(1)
    iscolumn(["s"; "t"; "u"])
    iscolumn(rand(3,1,1))
    iscolumn(rand(1,1,3))
    s = struct();
    iscolumn(s) // Empty structure
    clear s
    s.a = %z;
    s.b = 2;
    iscolumn(s) // Scalar array of structures
    clear s
    s(2,1).a = "w";
    s(3,1).b = %t;
    iscolumn(s) // Column array of structures
    clear s
    s(1,2).a = -2;
    s(3,1).b = %pi;
    iscolumn(s) // 2D array of structures
    clear s
    s(1,1,2).a = 3;
    s(1,1,3).b = "test";
    iscolumn(s) // 3D array of structures (with 2 singleton dims)

## See also

- isscalar
- isrow
- ismatrix
- issquare
- isempty

## History

5.5.0 Function iscolumn introduced.