I have a file called “run.jl” which has a function “update”. I have a main function which create matrix “Record”, which needs to be updated in a for loop. However, the matrix is not updated. What is the best way to update it with defining it as global variable? #run.jl function update(Record,iter) …

The matrix Record is not updated, because you are not updating it. [image] Amro: Record += Record*iter; does not update Record, but instead creates a new matrix, which has a value equal to Record + Record*iter. If you want to update it you must do it in-place, which you can achieve with .= …

I got it, thank you very much! Given that: Record = [1,2;3,4]; which method below is faster (In terms of performance): for _ in 1:100 Record .= Record*iter + Record*50 ; # Method-1 Record[:] = Record[:]*iter + Record[:]*50; # Method-2 end

Neither of them is good. The last line is definitely bad, but also in the first one you forget dots, and do unnecessary operations. [image] Amro: Record .= Record*iter + Record*50 should rather be Record .= Record .* iter .+ Record .* 50 Make sure all dots are there. But it’s better to do …

Thank you! Actually, I tried to shorten the scheme. The original is: Record = [1,2;3,4]; SS = [3,4;5,6]; iter = 0; for _ in 1:100 iter += 1; Record .= Record .* iter .+ SS .* 50 ; end

That’s a bit harder to simplify, at least for my vacation brain😎 But at least you can do for iter in 1:100 instead of iter += 1 inside the loop body.

Lol, thank you. I really appreciate your help during vacation.

What is the best way to update matrix in callable function?

General Usage

acxz July 23, 2022, 2:29am 10

For a solution to a similar problem to this see the following comment; How to build this sparsematrix in Julia - #9 by acxz

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What is the best way to update matrix in callable function?

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