# Help with JuMP

**URL:** <https://discourse.julialang.org/t/help-with-jump/53724>\
**Category:** Optimization (Mathematical)\
**Tags:** question, jump\
**Created:** [January 21, 2021, 1:39pm UTC](https://discourse.julialang.org/t/help-with-jump/53724 "2021-01-21T13:39:59Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![RaquelSantos](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/raquelsantos/32/3668_2.png) [@RaquelSantos](https://discourse.julialang.org/u/RaquelSantos)\
**Post date:** [January 21, 2021, 1:40pm UTC](https://discourse.julialang.org/t/help-with-jump/53724/1 "2021-01-21T13:40:00Z")

</div>

Hello  
I’m trying to make the “for” compile all the variables in the model, but whenever I compile it just returns the variable “c”  
Can anybody help me ?  
Thank you!!

```julia
using JuMP, MathOptInterface, GLPK, GLPKMathProgInterface
ModeloD = Model(solver = GLPKSolverMIP())

a = 4
t = 4
w = 2

A = 1:a
T = 1:t
W = 1:w

NE = [14, 53]
WH = [2489 1447 3513 20914; 11073 5414 1523 16282]
CR = [11, 12]
CO = [50, 51]

var = @variable(ModeloD,c[A],Bin)
var = @variable(ModeloD,r[A,T] <=0)
var = @variable(ModeloD,wo[W,T]>=0)
var = @variable(ModeloD,wr[W,T]<=0)
var = @variable(ModeloD,er[W,T]<=0)
var = @variable(ModeloD,eo[W,T]<=0)
var = @variable(ModeloD,s[A,T]<=0)
var = @variable(ModeloD,x[A,T]<=0)

@objective(ModeloD,Min,sum(CR[w]*(wr[w,t]+wo[w,t])+CO[w]*wo[w,t] for w in W, t in T))

for w = 1:w, t= 1:t
    n= @constraint(ModeloD, er[w,t]<= NE[w])
    #println(n)
end

for w = 1:w,t= 1:t
    h = @constraint(ModeloD,eo[w,t]<=NE[w])
    #println(h)
end

for w = 1:w,t= 1:t
    ç = @constraint(ModeloD,wr[w,t]+wo[w,t]==WH[w,t])#25
    #println(ç)
end

print(ModeloD)
status = solve(ModeloD)
println("Objective value: ", JuMP.getobjectivevalue(ModeloD))

#Compile all model variables
for w = 1:w, a = 1:a, t= 1:t
    pp = JuMP.getvalue(var)
    println(pp)
end

#The previous "for" should compile all of these variables
println("c = ", JuMP.getvalue(c))
println("r = ", JuMP.getvalue(r))
println("o = ", JuMP.getvalue(o))
println("wo = ", JuMP.getvalue(wo))
println("wr = ", JuMP.getvalue(wr))
println("er = ", JuMP.getvalue(er))
println("eo = ", JuMP.getvalue(eo))
println("s = ", JuMP.getvalue(s))
println("x = ", JuMP.getvalue(x))

```

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<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 21, 2021, 4:02pm UTC](https://discourse.julialang.org/t/help-with-jump/53724/2 "2021-01-21T16:02:26Z")

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Your code is nonsensical.

`var` is a name that points to some object. You create `var` initially pointing to variable `c`, then you change it to point to `r`, and then to `wo`, and so on. The value inside `var` at the end of your `@variable` block will always be the last variable `x` (not `c`) because it was the last thing you put inside `var` was `x`.

Your `for` loop iterates `w = 1:w, a = 1:a, t= 1:t` but none of these indexes are used to index `var` so they serve no purpose besides printing `var` over and over. Also, it is not good style to use the same variable as iterator and end of the range (even if it works).

Your syntax shows that you are using JuMP `0.18`, as I already said before, if possible use latest version `0.21` instead.

What you seem to want is to save all variables in a structure to print later, and you can do so this way:

```julia

jump_vars = Dict{Symbol, Any}()
jump_vars[:c] = @variable(ModeloD,c[A],Bin)
jump_vars[:r] = @variable(ModeloD,r[A,T] <=0)
# ... and so on, do this for all @variable
# and then in your loop do:
for (curr_name, curr_var) in jump_vars
    println("$curr_name = ", JuMP.getvalue(curr_var))
end

```

Probably there better ways to do this in Julia `0.21`, maybe even in `0.18` but then I would need to re-read the old documentation.

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<div class="post-metadata">

**Author:** ![RaquelSantos](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/raquelsantos/32/3668_2.png) [@RaquelSantos](https://discourse.julialang.org/u/RaquelSantos)\
**Post date:** [January 21, 2021, 8:17pm UTC](https://discourse.julialang.org/t/help-with-jump/53724/3 "2021-01-21T20:17:44Z")

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Hi, @Henrique_Becker  
thank you so much for your help, I’m starting to program in Julia and once your suggestion worked. Thank you!

As you said, the idea really is this, to save all variables in a structure to print on a dataframe, which is another thing I’m trying to do.

I already tried to update JuMP to version `0.21` and I couldn’t.

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<div class="post-metadata">

**Author:** ![Henrique\_Becker](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/henrique_becker/32/15443_2.png) [@Henrique\_Becker](https://discourse.julialang.org/u/Henrique_Becker)\
**Post date:** [January 21, 2021, 8:40pm UTC](https://discourse.julialang.org/t/help-with-jump/53724/4 "2021-01-21T20:40:28Z")

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I forgot to continue answering your question about JuMP version, I will return to it.

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<div class="post-metadata">

**Author:** ![RaquelSantos](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/raquelsantos/32/3668_2.png) [@RaquelSantos](https://discourse.julialang.org/u/RaquelSantos)\
**Post date:** [January 25, 2021, 2:42pm UTC](https://discourse.julialang.org/t/help-with-jump/53724/5 "2021-01-25T14:42:45Z")

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Hello everybody  
I would like the “for” to write the results of all variables in a DataFrame with extension for a .CSV, but when I compile the model, the “for” displays this error message  
`MethodError: no method matching setindex!`

`:resultvariablet` is the name of the CSV field that I need to fill out.

```julia
for row in CSV.Rows ("file.csv")
     Result [c,: resultvariable] = JuMP.getvalue (jump_vars [:c])
     #println ("c =", JuMP.getvalue (jump_vars [: c])) #this attempt does not present an error but also does not write in the datafrema
     #print ("c = $ (JuMP.getvalue (c))") # this attempt does not present an error but also does not write in the datafrema
end

```

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<div class="post-metadata">

**Author:** ![nilshg](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nilshg/32/2283_2.png) [@nilshg](https://discourse.julialang.org/u/nilshg)\
**Post date:** [January 25, 2021, 4:12pm UTC](https://discourse.julialang.org/t/help-with-jump/53724/6 "2021-01-25T16:12:40Z")

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You don’t have a `DataFrame`, but a `CSV.Rows` iterator? Also, you don’t use the `row` which you take from the iterator in your loop?

There are also multiple syntax errors in your code - you can’t have whitespace between a function/constructor name and the opening brackets for the arguments when calling it, so `CSV.Rows ("myfile.csv")` errors, as you need `CSV.Rows("myfile.csv")`

Also, this question doesn’t have anything to do with `JuMP` from what I can tell, as it sounds like you’re able to extract the value you want from your model, you just don’t know how to save it into a DataFrame? In that case I would recommend opening a new topic with your specific question and a minimum reproducible example (using just CSV and DataFrames, as it appears JuMP is just a distraction here)