# Error code for GLPK and SigmoidalProgramming

**URL:** <https://discourse.julialang.org/t/error-code-for-glpk-and-sigmoidalprogramming/98043>\
**Category:** Optimization (Mathematical)\
**Tags:** package, jump, optimization\
**Created:** [April 28, 2023, 2:03pm UTC](https://discourse.julialang.org/t/error-code-for-glpk-and-sigmoidalprogramming/98043 "2023-04-28T14:03:20Z")\
**Posts on this page:** 1\
**Showing post:** 4

<div class="post-metadata">

**Author:** ![meet.saiya](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/meet.saiya/32/49312_2.png) [@meet.saiya](https://discourse.julialang.org/u/meet.saiya)\
**Post date:** [April 30, 2023, 8:32am UTC](https://discourse.julialang.org/t/error-code-for-glpk-and-sigmoidalprogramming/98043/4 "2023-04-30T08:32:30Z")

</div>

I think the issue originates in defining functions in list. The fs and dfs passed in the example are of function type whereas what I was passing was something else. I’m still trying to figure it out.  
More about the issue: [Another community post : )](https://discourse.julialang.org/t/what-are-different-types-of-functions-in-julia-and-what-are-the-differences-between-them/98113)

I got as far as defining the functions as `fs(x::Number, b::Number) = x^b` and `dfs(x::Number, b::Number) = b*x^(b-1)` but I don’t know how to fill them in a vector or specific length. What I eventually want is a vector\list like [c1.f1 c2.f2 c3.f3…cn.fn] where ci is cost and fi is fs defined here. I also expect another error here that since b is a parameter I define earlier, and use it in this code, I want to just pass in b, but it’s not a number and I suspect it throwing up error.

Kindly let me know how to get around this. Any help is deeply appreciated!

---

_[View the full topic](https://discourse.julialang.org/t/error-code-for-glpk-and-sigmoidalprogramming/98043)._