python - Iterate permutation per row per item

Question

I would like to manipulate data to do network analysis using ggnet.

The dataset is in csv form and looks like this:

offers
{9425, 5801, 18451, 17958, 16023, 7166}
{20003, 17737, 4031, 5554}
{19764, 5553, 5554}

What I would like to break the array, and iterate to permute all the items each row as a pair of 2. So the ultimate output should look like:

print list(itertools.permutations([1,2,3,4], 2)) per row to create: 

(9425, 5801)
(9425, 18451)
(9425, 17958)
(9425, 16023)
(9425, 7166)
(5801, 18451)
(5801, 17958)
(5801, 16023)
(5801, 7166)
...

I could use either R or Python to do this. Any suggestions to solve this problem?

Answer 1

Another R solution, assuming there are more rows in your file.

# read in csv file as list of integers (each row in csv = 1 list element)
offers <- readLines("offers.csv") %>% strsplit(",") %>% lapply(as.integer)

# create permutation pairs for each element in the list
permutation.list <- lapply(seq_along(offers), function(i) {t(combn(offers[[i]], m = 2))})

# combine all permutation pairs into 1 data frame
permutation.data.frame <- plyr::ldply(permutation.list, data.frame)

Below are the results based on the sample data provided:

> permutation.list
[[1]]
       [,1]  [,2]
 [1,]  9425  5801
 [2,]  9425 18451
 [3,]  9425 17958
 [4,]  9425 16023
 [5,]  9425  7166
 [6,]  5801 18451
 [7,]  5801 17958
 [8,]  5801 16023
 [9,]  5801  7166
[10,] 18451 17958
[11,] 18451 16023
[12,] 18451  7166
[13,] 17958 16023
[14,] 17958  7166
[15,] 16023  7166

[[2]]
      [,1]  [,2]
[1,] 20003 17737
[2,] 20003  4031
[3,] 20003  5554
[4,] 17737  4031
[5,] 17737  5554
[6,]  4031  5554

[[3]]
      [,1] [,2]
[1,] 19764 5553
[2,] 19764 5554
[3,]  5553 5554

> permutation.data.frame
      X1    X2
1   9425  5801
2   9425 18451
3   9425 17958
4   9425 16023
5   9425  7166
6   5801 18451
7   5801 17958
8   5801 16023
9   5801  7166
10 18451 17958
11 18451 16023
12 18451  7166
13 17958 16023
14 17958  7166
15 16023  7166
16 20003 17737
17 20003  4031
18 20003  5554
19 17737  4031
20 17737  5554
21  4031  5554
22 19764  5553
23 19764  5554
24  5553  5554