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kotlinlang

I'm trying to do matrix multiplication in multik (<https://github.com/Kotlin/multik>). It seems like I should get a 2 X 3 matrix, but I get an error message that says "Array shapes don't match: [2, 1] != [1, 3]". Can anyone say if this is a bug or am I doing something horribly wrong?

```val a = mk.ndarray(floatArrayOf(1.0f, 2.0f), 2, 1)
val b = mk.ndarray(floatArrayOf(1.0f, 2.0f, 3.0f), 1, 3)

val result = a * b
println(result)```


They are not matrices, they are nd arrays. Multik works in numpy paradigm where multiplication is element by element. You need to use `dot` operation to dot operation for matrix product.

There are three different ways to separate element-by-element behavior from matrix behavior:
1. Use different operators on the same structures.
2. Use different types (for example wrap 2d ndarray in a Matrix type).
3. Use different context for those operations.
Multik uses variant 1.

That makes sense, thanks a lot for the help.