Why didn't I get an error for my matrices?

So I created a 3x3 matrix and created another 3x1 matrix. I thought adding matrices with different dimensions should result in an error but when I performed the addition it added the 3x1 matrix to the first column of the 3x3 matrix. Why did MATLAB do this?

Answer 1

[madhan ravi]

https://www.mathworks.com/help/matlab/matlab_prog/array-vs-matrix-operations.html

Answer 2

[Star Strider]

You are seeing ‘Automatic Implicit Expansion’ introduced in R2016b (much to the consternation of many of us). Previously, the operation you wrote would have thrown an error, and to get the result you did would have required using the bsxfun function.

Note that it added the column vector ‘b’ to every column of your (3x3) matrix ‘A’, not only the first column.