JuMP @Variable

Specific Domains Optimization (Mathematical)
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1

Hi,
I am solving an optimization problem with jump using the following table:

Row │ time  room_1   room_2   room_3   w_day     
     │ Float64  Float64  Float64  Float64  String  
─────┼─────────────────────────────────────────────
   1 │    10.0      2.0      1.0      5.0  Monday
   2 │    11.0      3.0      1.0      6.0  Monday

I need to create a binary variable x[time,room,w_day], my problem is that for time 10 I can only have courses 2, 1 and 5. that would get me x[10,2,Monday], x[10,1,Monday] and x[10,5,Monday].
Usually I make the variable, like:

@variable(model, x[10,[1,2,5],"Monday"], Bin)

But JuMP is interpreting the string as a list of strings and giving me the following:

x[10,1,M] binary
 x[10,2,M] binary
 x[10,5,M] binary
 x[10,1,o] binary
 x[10,2,o] binary
 x[10,5,o] binary
 x[10,1,n] binary
 x[10,2,n] binary
 x[10,5,n] binary
 x[10,1,d] binary
 x[10,2,d] binary

What am I doing wrong?
Thank you!

2

JuMP interprets "Monday" as an index set (it’s an iterable object). If you want a one-element set, write ["Monday"] instead, i.e., @variable(model, x[10,[1,2,5],["Monday"]], Bin).

3 Likes
3

Thank you! I knew I was missing something.

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