# If condition in constraint set

**URL:** <https://discourse.julialang.org/t/if-condition-in-constraint-set/22057>\
**Category:** Optimization (Mathematical)\
**Created:** [March 19, 2019, 3:20pm UTC](https://discourse.julialang.org/t/if-condition-in-constraint-set/22057 "2019-03-19T15:20:49Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![ilias](https://avatars.discourse-cdn.com/v4/letter/i/3bc359/32.png) [@ilias](https://discourse.julialang.org/u/ilias)\
**Post date:** [March 19, 2019, 3:20pm UTC](https://discourse.julialang.org/t/if-condition-in-constraint-set/22057/1 "2019-03-19T15:20:50Z")

</div>

Is there a way to rewrite the following constraint set in one row?

```julia
for i in set_i
    for ii in set_i
        if parameter[ii] >= parameter[i]
            @constraint( model, x[i] - y[ii] <= 0 );
        end
    end
end

```

Something like this:

```julia
@constraint( model, constrname[i in set_i, ii in set_i],
                x[i] - y[ii] <= 0 if parameter[ii] >= parameter[i] );

```

---

<div class="post-metadata">

**Author:** ![odow](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/odow/32/28685_2.png) [@odow](https://discourse.julialang.org/u/odow)\
**Post date:** [March 19, 2019, 3:37pm UTC](https://discourse.julialang.org/t/if-condition-in-constraint-set/22057/2 "2019-03-19T15:37:33Z")

</div>

See the JuMP docs: [Constraints · JuMP](http://www.juliaopt.org/JuMP.jl/latest/constraints/#SparseAxisArrays-1)

Admittedly, it isn’t a big section. If you wanted to expand them, you can edit the docs using this link [https://github.com/JuliaOpt/JuMP.jl/edit/master/docs/src/constraints.md](https://github.com/JuliaOpt/JuMP.jl/edit/master/docs/src/constraints.md)