10 Julia Recipes You Can't Miss

[VinodV]

@alfaromartino

function foo(x)
    output = similar(x)
    
    for i in eachindex(x)
        output[i] = x[i] + 1
    end

    return output
end

The second solution seems to be more efficient. Isn’t it.

 @time b = foo(1:100) #first one
  0.000023 seconds (1 allocation: 896 bytes)

 @time b = foo(1:100) #second one
  0.000008 seconds (1 allocation: 896 bytes)

[alfaromartino]

There should be no difference, or at most a negligible difference.

Recall that to compute times, either use @time and execute the function at least twice (the first run is always polluted by compilation time). But to do serious benchmarks, use the package BenchmarkTools and @btime. This computes multiple times the calculation to provide a more accurate benchmark.

[lostella]

Something I find extremely useful for reading files: eachline I/O and Network · The Julia Language

Also note that reverse needs to be qualified as Iterators.reverse in recent Julia versions.

Edit: Note however that reverse will not work with eachline, unlike Iterators.reverse.

[VinodV]

Updated in the article.

[Eben60]

For h. - see also Why are there all these strange stumbling blocks in Julia? - #67 by Eben60

e.g.

function retMultipleValues()
    v1,v2 = "India","Iran"
    return (; v1,v2)
end

[Eben60]

Also, you might want to link this thread: Seven Lines of Julia (examples sought)

[GunnarFarneback]

@lostella

Also note that reverse needs to be qualified as Iterators.reverse in recent Julia versions.

That doesn’t sound right. You might mean that Iterators.reverse knows how to reverse eachline iterators in recent Julia versions. reverse from Base has never known how to do that.

[lostella]

Yes, that’s right, my bad

[VinodV]

Now updated to include around 21 recipes. Please give feedback on items 11-21.