# Error with building NLexpression in JuMP 0.19.2

**URL:** <https://discourse.julialang.org/t/error-with-building-nlexpression-in-jump-0-19-2/26998>\
**Category:** Optimization (Mathematical)\
**Created:** [July 30, 2019, 9:29pm UTC](https://discourse.julialang.org/t/error-with-building-nlexpression-in-jump-0-19-2/26998 "2019-07-30T21:29:14Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**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:** [July 31, 2019, 6:39am UTC](https://discourse.julialang.org/t/error-with-building-nlexpression-in-jump-0-19-2/26998/2 "2019-07-31T06:39:49Z")

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Hi there!

Please read [Please read: make it easier to help you](https://discourse.julialang.org/t/psa-make-it-easier-to-help-you/14757) and provide a minimal working example that reproduces the same error.

However, that looks like a bug because you should probably get a nicer error message. It might be because of the `prod2.get`. What happens if you try:

```nohighlight
prod2_get = [prod2.get([m-1, m-1]) for m in 1:num_basis]
@NLexpression(model, [i = 1:num_buses], sum(
    prod2_get[m] * (vre_coeffs[i, m]^2 + vim_coeffs[i, m]^2) 
    for m = 1:num_basis)
)

```

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_[View the full topic](https://discourse.julialang.org/t/error-with-building-nlexpression-in-jump-0-19-2/26998)._