Creating NaN vector in MatLab

I know that these two functions: zeros() and ones() can be used to create a series of '0's and '1's in MatLab. For example:

a = zeros(5,1)
b = ones(7)

I just learned about another function today: NaN(). This function can create a vector or matrix with all the elements equals to nan. This is useful if you want to add a new empty column to a dataset, or table.

c = NaN(4,5)