# Can't figure out why this code isn't working

**URL:** <https://discourse.julialang.org/t/cant-figure-out-why-this-code-isnt-working/68546>\
**Category:** General Usage\
**Tags:** dictionary, string-dist\
**Created:** [September 21, 2021, 7:24pm UTC](https://discourse.julialang.org/t/cant-figure-out-why-this-code-isnt-working/68546 "2021-09-21T19:24:28Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![mthelm85](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mthelm85/32/224164_2.png) [@mthelm85](https://discourse.julialang.org/u/mthelm85)\
**Post date:** [September 21, 2021, 7:24pm UTC](https://discourse.julialang.org/t/cant-figure-out-why-this-code-isnt-working/68546/1 "2021-09-21T19:24:28Z")

</div>

```julia
using CSV
using StringDistances
using Unicode

data = CSV.File(raw"C:\Users\mthel\Julia\src_data\data.csv", normalizenames=true)

data = clean_strings(data[i][2] for i in 1:200)

function build_dict(data)
    dict = Dict(data[1] => [])

    for i in 2:length(data), (key, value) in dict
        if compare(data[i], key, Levenshtein()) > 0.7
            push!(value, data[i])
        else
            dict[data[i]] = []
        end
    end
    
    dict
end

dict = build_dict(data)

```

When I examine the keys of `dict`, I see that the following strings have ended up as keys:

```julia
TRAFFICCONTROLTECH
TRAFFICCONTROLTEHC
TRAFFICCONTROTECH

```

but the Levenshtein similarity scores are all higher than the specified threshold of 0.7 (on line 13).

```julia
julia> compare("TRAFFICCONTROLTECH", "TRAFFICCONTROLTEHC", Levenshtein())
0.8888888888888888

julia> compare("TRAFFICCONTROLTECH", "TRAFFICCONTROTECH", Levenshtein())
0.9444444444444444

```

Only one of these should have ended up as a key and the other two should have been detected in the `if` clause and subsequently pushed to the `value` associated with the existing key. I’m stumped as to why this is happening. There has to be a silly mistake somewhere that I’m missing…

---

<div class="post-metadata">

**Author:** ![cjdoris](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/cjdoris/32/213133_2.png) [@cjdoris](https://discourse.julialang.org/u/cjdoris)\
**Post date:** [September 21, 2021, 7:36pm UTC](https://discourse.julialang.org/t/cant-figure-out-why-this-code-isnt-working/68546/2 "2021-09-21T19:36:05Z")

</div>

The main error is that you’re keeping any value whose distance is at least 0.7 from at least one key, whereas I assume you’re intending to keep those whose distance is at least 0.7 from all keys.

Also you shouldn’t modify a dict while iterating over it.

---

<div class="post-metadata">

**Author:** ![oheil](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/oheil/32/220745_2.png) [@oheil](https://discourse.julialang.org/u/oheil)\
**Post date:** [September 21, 2021, 7:36pm UTC](https://discourse.julialang.org/t/cant-figure-out-why-this-code-isnt-working/68546/3 "2021-09-21T19:36:50Z")

</div>

> [@mthelm85](#):
>
> `for i in 2:length(data), (key, value) in dict`

You compare every data[i] to every (key,value) pair, so there is always one with distance y\< 0.7

(ninjad)

---

<div class="post-metadata">

**Author:** ![mthelm85](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mthelm85/32/224164_2.png) [@mthelm85](https://discourse.julialang.org/u/mthelm85)\
**Post date:** [September 21, 2021, 7:39pm UTC](https://discourse.julialang.org/t/cant-figure-out-why-this-code-isnt-working/68546/4 "2021-09-21T19:39:48Z")

</div>

> [@cjdoris](#):
>
> Also you shouldn’t modify a dict while iterating over it.

Which data structure should I use for this type of operation?

---

<div class="post-metadata">

**Author:** ![oheil](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/oheil/32/220745_2.png) [@oheil](https://discourse.julialang.org/u/oheil)\
**Post date:** [September 21, 2021, 7:48pm UTC](https://discourse.julialang.org/t/cant-figure-out-why-this-code-isnt-working/68546/5 "2021-09-21T19:48:31Z")

</div>

In this case you can stay with a dict as you don’t need to modify it while iterating:

```julia
    for i in 2:length(data)
		similarindex = 0
		for (key, value) in dict
			if compare(data[i], key, Levenshtein()) > 0.7
				similarindex = i
				break
			end
		end
		if similarindex > 0
			push!(value, data[similarindex])
		else
			dict[data[i]] = []
		end
    end

```

didn’t tested, hope it works like that.