Building up a list of dictionaries from a few lists in Python

Question

I have a few lists like this:

Pargs = [args.Pee, args.Pem,...,args.Pet] # 9 elements of boolean type
indices = [(0,0),(0,1),...,(2,2)] # 9 possible combinations (i,j), i = 0,1,2; j = 0,1,2
D = [{},{},...,{}] # 9 dictionaries, desired result

The result I want to see should look like this:

D = [{event:args.Pee,i:0,j:0},{event:args.Pem,i:0,j:1},...{event: args.Pet,i:2,j:2}]

The dictionaries must be ordered like shown above.

I tried

for d in D:
    for i in range(3):
        for j in range(3):
            d['i'],d['j'] = i,j

but it does not do the trick. I've tried numerous algorithms with zip(),product(),dict(), but to no avail...

Answer 1

With a comprehension and OrderedDict, demo:

from collections import OrderedDict
pargs = ['arg1', 'arg2', 'arg3', 'arg4', 'arg5', 'arg6', 'arg7', 'arg8', 'arg9']
indices = ((x,y) for x in range(3) for y in range(3))
result = [OrderedDict([('event',p), ('i',i), ('j',j)]) for p,(i,j) in zip(pargs, indices)]
print(result) # [OrderedDict([('event', 'arg1'), ('i', 0), ('j', 0)]), OrderedDict([('event', 'arg2'), ('i', 0), ('j', 1)]), OrderedDict([('event', 'arg3'), ('i', 0), ('j', 2)]), OrderedDict([('event', 'arg4'), ('i', 1), ('j', 0)]), OrderedDict([('event', 'arg5'), ('i', 1), ('j', 1)]), OrderedDict([('event', 'arg6'), ('i', 1), ('j', 2)]), OrderedDict([('event', 'arg7'), ('i', 2), ('j', 0)]), OrderedDict([('event', 'arg8'), ('i', 2), ('j', 1)]), OrderedDict([('event', 'arg9'), ('i', 2), ('j', 2)])]

edit

If I misunderstood your requirements and the order within the dictionaries does not matter, you can do it without an OrderedDict like this:

result = [{'event':p, 'i':i, 'j':j} for p,(i,j) in zip(pargs, indices)]

Answer 2

From the looks of your question, you're looking to do something like the following:

>>> Pargs = [str(i) for i in range(9)]
>>> Pargs
9: ['0', '1', '2', '3', '4', '5', '6', '7', '8']
>>> indeces = [(i, j) for i in range(3) for j in range(3)]
10: [(0, 0), (0, 1), (0, 2), (1, 0), (1, 1), (1, 2), (2, 0), (2, 1), (2, 2)]
>>> D = [{'event':Pargs[ind], 'i':i[0], 'j':i[1]} for ind, i in enumerate(indeces)]
>>> D
11: [{'event': '0', 'i': 0, 'j': 0},
 {'event': '1', 'i': 0, 'j': 1},
 {'event': '2', 'i': 0, 'j': 2},
 {'event': '3', 'i': 1, 'j': 0},
 {'event': '4', 'i': 1, 'j': 1},
 {'event': '5', 'i': 1, 'j': 2},
 {'event': '6', 'i': 2, 'j': 0},
 {'event': '7', 'i': 2, 'j': 1},
 {'event': '8', 'i': 2, 'j': 2}]
>>> 

The key you seemed to be missing in your attempts was to iterate through indeces and Pargs at the same time.