lensize.md

Length and Size

len(a)

len returns the length of a collection.

len(1)                              =>  1
len(1:10)                           => 10
len("abc")                          =>  3
len(["a",1])                        =>  2
len(ones(2,3))                      =>  3
len(ones(2,3,4))                    =>  4

siz(a)

siz returns the size of an item. Items always have at least 2 dimensions. For arrays siz(a) == col(size(a)).

siz(1)                              =>  [1 1]'
siz(1:5)                            =>  [1 5]'
siz("abc")                          =>  [1 3]'
siz(["a",1])                        =>  [2 1]'
siz(["a" 1])                        =>  [1 2]'
siz(ones(2,3))                      =>  [2 3]'
siz(ones(2,3,4))                    =>  [2 3 4]'

siz3(a)

siz3 works for arrays with ndims<=3 and always returns a 3 x 1 vector. This can help in using the same code for 2D and 3D data.

siz3(ones(1))                       => [1 1 1]'
siz3(ones(1,2))                     => [1 2 1]'
siz3(ones(1,2,3))                   => [1 2 3]'