Creating a tuple from combination of tuple and vectors

Specific Domains Optimization (Mathematical)
, , ,
1

I’d like to combine three thing; a Vector{Tuple{Int64, Int64}}, Vector{Vector{Int64}}, and a Vector{Int64} under some condition to be able to create a new tuple; in other words; a Vector{Tuple{Int64, Int64, Int64}}. And then define a variable x(i,j,k) on them.

For example, if we have the following:

# A is the condition
A = [(1, 2), (1, 3),
       (2, 1), (2, 7), (2, 8), (2, 4), 
       (3, 4), (3,5), (4,3) (4,2), (4,6),(4,9),
       (5,6), (7,8), (7,10), (8,9), (8,10), (9,10)]

# These are thing that we want to combine them           
B = [ 2,9]
C = [ [1,7,3,4], [4,10,1,2,6,7]]
D = [12,15]

We are interested in a tuples like (i,j,k) which satisfy these conditions: i in B , j in C, k in D and (i,j) in A

In the above case, therefore will result in the following:

 
[   # for  k =12 
     [(2,1,12), (2,7,12), (2,4,12)] , 
     # for k =15  
     [(9,10,15)]

  ]

I’ve trired to first filter out those combination of (i,j) which are satisfy three condition of i in B && j in C && (i,j) in A and then put them together with additional index over k in D. But it throw an error every time.

Do you know of any better way?

2

Hi @joxane7887, welcome to the community :slight_smile:

By looking at the example that you have provided, i assumed length(B) == length(C) == length(D) and came up with the below impl → 

for (idx, i) in enumerate(B)
    for j in C[idx]
        (i, j) in A && println((i, j, D[idx]))
    end
end

output → 

(2, 1, 12)
(2, 7, 12)
(2, 4, 12)
(9, 10, 15)

I’m not sure if this is what you are expecting …!!

1 Like
3

Hi @Karthik-d-k Thanks. I’m a beginner, and didn’t know about enumerate. So, How is it possible to use @variable macro and define a x(i,j,k) with this indicies?

Why this one is incorrect?
@variable(model, x[ (i, j, k) for (idx, i) in enumerate(B) for j in C[idx] && (i, j) in A for k in D[idx] ] >= 0, Bin)

4

Is this question related to Define variables on each elemnts of a vector of vectors? It seems pretty similar.

A = [
    (1, 2), (1, 3), (2, 1), (2, 7), (2, 8), (2, 4), (3, 4), (3, 5), (4, 3), 
    (4, 2), (4, 6), (4, 9), (5, 6), (7, 8), (7, 10), (8, 9), (8, 10), (9, 10),
]
B = [2, 9]
C = [[1, 7, 3, 4], [4, 10, 1, 2, 6, 7]]
D = [12, 15]

using JuMP
model = Model()
sets = [(b, c, d) for (k, d) in enumerate(D) for b in B for c in C[k] if (b, c) in A]
@variable(model, x[sets])
x[(2, 7, 12)]
2 Likes
5

Quite beautiful! @odow Super thanks for this and link. I didn’t know about that.
The output of @Karthik-d-k is theone I’m trying to put in your format. sets contains those combination that satisfys all things and in your definition 7-element Vector{Tuple{Int64, Int64, Int64}}: However, it should be 4-element Vector{Tuple{Int64, Int64, Int64}}: or `like the original following format

[   # for  k =12 
     [(2,1,12), (2,7,12), (2,4,12)] , 
     # for k =15  
     [(9,10,15)]

  ]

I was unable spot the issue in your code ( could the issue be because of (b, c) in A)?

1 Like
6

This will give you Vector{Tuple{Int64, Int64, Int64}} → 

[(i, j, D[idx]) for (idx, i) in enumerate(B) for j in C[idx] if (i, j) in A]
2 Likes