# Adding JuMP variable via list of tuples (Specify dimensions using tuples)

**URL:** <https://discourse.julialang.org/t/adding-jump-variable-via-list-of-tuples-specify-dimensions-using-tuples/14867>\
**Category:** Optimization (Mathematical)\
**Tags:** jump\
**Created:** [September 12, 2018, 4:16pm UTC](https://discourse.julialang.org/t/adding-jump-variable-via-list-of-tuples-specify-dimensions-using-tuples/14867 "2018-09-12T16:16:18Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![skam](https://avatars.discourse-cdn.com/v4/letter/s/9fc348/32.png) [@skam](https://discourse.julialang.org/u/skam)\
**Post date:** [September 12, 2018, 4:16pm UTC](https://discourse.julialang.org/t/adding-jump-variable-via-list-of-tuples-specify-dimensions-using-tuples/14867/1 "2018-09-12T16:16:18Z")

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Hi,

I was wondering whether there is a smart solution for adding variables with “nonsquare” dimensions.  
A minimal example:

```julia
using JuMP

testset=[("a","b"), ("c","d")]
indices=["a","b","c","d"]

m = Model()

v=@variable(m,
            v[
            i1 in indices,
            i2 in indices;
            (i1,i2) in testset]
            )

print(v["a","b"])

```

Now I am looking for a more convenient way for adding the variable v just for the indices [“a”,“b”] and [“c”, “d”], e.g. something like that (what will raise an error)

```julia
v2=@variable(m,
            v[(i1,i2)... for [i1,i2] in testset]
            )

```

---

<div class="post-metadata">

**Author:** ![bbrunaud](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/bbrunaud/32/1737_2.png) [@bbrunaud](https://discourse.julialang.org/u/bbrunaud)\
**Post date:** [September 14, 2018, 4:05am UTC](https://discourse.julialang.org/t/adding-jump-variable-via-list-of-tuples-specify-dimensions-using-tuples/14867/2 "2018-09-14T04:05:12Z")

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Hi, this was already asked and solved. Search the forum