Size function - Dimensions of matrix:
For the matrix mat shown next, it has three rows and two columns, therefore the size is 3 × 2. The length is the larger dimension that is 3.
>> mat = [1:3; 5:7]'
>> [r c] = size(mat)
r = 3
c = 2
The size function returns two values; therefore in order to capture these values in separate variables we put a vector of two variables on the left of the assignment. The variable r stores the initial value returned, that is the number of rows, and c stores the number of columns.