# Iteration in for loop

**URL:** <https://discourse.julialang.org/t/iteration-in-for-loop/62207>\
**Category:** New to Julia\
**Tags:** question\
**Created:** [June 1, 2021, 4:21pm UTC](https://discourse.julialang.org/t/iteration-in-for-loop/62207 "2021-06-01T16:21:23Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![assia855](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/assia855/32/22845_2.png) [@assia855](https://discourse.julialang.org/u/assia855)\
**Post date:** [June 1, 2021, 4:21pm UTC](https://discourse.julialang.org/t/iteration-in-for-loop/62207/1 "2021-06-01T16:21:23Z")

</div>

Hello Folks,

I got a folder full of files. I would like to iterate 5 times each file in the folder. I got this bellow code, but I don’t have idea how to iterate 5 times each file in the folder.

```julia
DISK = glob("disk/*")

for files in DISK

		DISKS = read(FitsArray, files);
		Iu=gain .* DISKS[:,:,1];
		
        write(FitsArray, Iu)
end

```

---

<div class="post-metadata">

**Author:** ![nilshg](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nilshg/32/2283_2.png) [@nilshg](https://discourse.julialang.org/u/nilshg)\
**Post date:** [June 1, 2021, 4:25pm UTC](https://discourse.julialang.org/t/iteration-in-for-loop/62207/2 "2021-06-01T16:25:38Z")

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What’s wrong with just

```julia
for files in DISK
    for i in 1:5
         [do whatever you have to do five times]
    end
end

```

?

---

<div class="post-metadata">

**Author:** ![assia855](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/assia855/32/22845_2.png) [@assia855](https://discourse.julialang.org/u/assia855)\
**Post date:** [June 1, 2021, 4:31pm UTC](https://discourse.julialang.org/t/iteration-in-for-loop/62207/3 "2021-06-01T16:31:46Z")

</div>

Thank you, and i where should I insert it to iterate 5 times

---

<div class="post-metadata">

**Author:** ![nilshg](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nilshg/32/2283_2.png) [@nilshg](https://discourse.julialang.org/u/nilshg)\
**Post date:** [June 1, 2021, 5:55pm UTC](https://discourse.julialang.org/t/iteration-in-for-loop/62207/4 "2021-06-01T17:55:49Z")

</div>

Where the square brackets are - a more complete example

```julia
julia> files = ["File $i" for i ∈ 1:3]
3-element Vector{String}:
 "File 1"
 "File 2"
 "File 3"

julia> for f ∈ files
           for i ∈ 1:5
               println("Working on file $f, iteration number $i")
           end
       end
Working on file File 1, iteration number 1
Working on file File 1, iteration number 2
Working on file File 1, iteration number 3
Working on file File 1, iteration number 4
Working on file File 1, iteration number 5
Working on file File 2, iteration number 1
Working on file File 2, iteration number 2
Working on file File 2, iteration number 3
Working on file File 2, iteration number 4
Working on file File 2, iteration number 5
Working on file File 3, iteration number 1
Working on file File 3, iteration number 2
Working on file File 3, iteration number 3
Working on file File 3, iteration number 4
Working on file File 3, iteration number 5

```