Array Operation Easy Question about formula.

Hello

Why this equation is possible to solve in the current matlab, despite the fact that a few years ago it was impossible ?

X = [ 1;2;3] Y = [ 4;5;6] X'.*Y.

MATLAB R202b

[Stephen23]

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[Stephen23]

Original question by Mateusz Zak:

Array Operation Easy Question about formula.

Hello

Why this equation is possible to solve in the current matlab, despite the fact that a few years ago it was impossible ?

X = [ 1;2;3] Y = [ 4;5;6] X'.*Y.

MATLAB R202b

Original comment by Mateusz Zak:

Sorry.

X = [ 1;2;3] Y = [ 4;5;6] X'.*Y

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[Ameer Hamza]

It was introduced in R2016b. Read all about it here: https://blogs.mathworks.com/loren/2016/10/24/matlab-arithmetic-expands-in-r2016b/. Previously such a thing was only possible through bsxfun().

[Ameer Hamza]

Yes, MATLAB automatically expand both matrices to have equal size and then use element-wise operation. In your case X' is [1x3] and Y is [3x1]. MATLAB repeat elements of X' and Y to make them 3x3 matrices.