# Identifying variables in GAMS.jl errors (how do I look up JuMP variables from auto-generated name x..)

**URL:** <https://discourse.julialang.org/t/identifying-variables-in-gams-jl-errors-how-do-i-look-up-jump-variables-from-auto-generated-name-x/74851>\
**Category:** Optimization (Mathematical)\
**Tags:** jump\
**Created:** [January 19, 2022, 7:28am UTC](https://discourse.julialang.org/t/identifying-variables-in-gams-jl-errors-how-do-i-look-up-jump-variables-from-auto-generated-name-x/74851 "2022-01-19T07:28:39Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![MartinBonde](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/martinbonde/32/33200_2.png) [@MartinBonde](https://discourse.julialang.org/u/MartinBonde)\
**Post date:** [January 19, 2022, 7:28am UTC](https://discourse.julialang.org/t/identifying-variables-in-gams-jl-errors-how-do-i-look-up-jump-variables-from-auto-generated-name-x/74851/1 "2022-01-19T07:28:39Z")

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I am sending a JuMP model to a GAMS solver using GAMS.jl and get an error/warning:  
`** Error in Square System: A variable tries to exceed its bound.`

This is perfectly familiar and I get more information by looking in the generated moi.lst file  
to find out which variable is the culprit:

```julia
**** ERRORS/WARNINGS IN VARIABLE x382
     1 error(s): The variable tries to exceed its bound.

```

Is there any way of identifying what “x382” refers to in the above?

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**Author:** ![miles.lubin](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/miles.lubin/32/279_2.png) [@miles.lubin](https://discourse.julialang.org/u/miles.lubin)\
**Post date:** [January 20, 2022, 3:20pm UTC](https://discourse.julialang.org/t/identifying-variables-in-gams-jl-errors-how-do-i-look-up-jump-variables-from-auto-generated-name-x/74851/2 "2022-01-20T15:20:00Z")

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I don’t know if the GAMS.jl authors follow discourse. I’d recommend opening an issue at [https://github.com/GAMS-dev/gams.jl/issues](https://github.com/GAMS-dev/gams.jl/issues). JuMP does provide the capability to pass variable names down to the solver.

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**Author:** ![MartinBonde](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/martinbonde/32/33200_2.png) [@MartinBonde](https://discourse.julialang.org/u/MartinBonde)\
**Post date:** [January 20, 2022, 8:21pm UTC](https://discourse.julialang.org/t/identifying-variables-in-gams-jl-errors-how-do-i-look-up-jump-variables-from-auto-generated-name-x/74851/3 "2022-01-20T20:21:34Z")

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Thanks for the suggestion, I have opened an issue here: [https://github.com/GAMS-dev/gams.jl/issues/12](https://github.com/GAMS-dev/gams.jl/issues/12)

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**Author:** ![renke.kuhlmann](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/renke.kuhlmann/32/15384_2.png) [@renke.kuhlmann](https://discourse.julialang.org/u/renke.kuhlmann)\
**Post date:** [January 26, 2022, 12:55pm UTC](https://discourse.julialang.org/t/identifying-variables-in-gams-jl-errors-how-do-i-look-up-jump-variables-from-auto-generated-name-x/74851/4 "2022-01-26T12:55:19Z")

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Thanks @miles.lubin for referring to the GAMS.jl repository. Indeed, I tend to miss things here. I’ll try to get better…