Question

I have a list of data from which I am creating dict inside dict, structure it is coming as expected but somewhere it is overwriting, I don’t know where

a=['t1_h1','t2_h2']
b=['h1_d1','h1_d2','h2_d3']
c=['d1_dom1','d2_dom2','d3_dom3']
d=['dom1_a','dom1_b','dom2_a','dom2_b','dom3_a','dom3_b']

I tried using this code

for item in a:
f[item.split('_')[0]]={}
for hypercube in b:
    if item.split('_')[1] in hypercube:#h1 in b

        f[item.split('_')[0]][item.split('_')[1]]={}

        for dimension in c:
            if hypercube.split('_')[1] in dimension:#d1 in c 
                f[item.split('_')[0]][item.split('_')[1]][hypercube.split('_')[1]]={}
                for domain in d:
                    if dimension.split('_')[1] in domain:#dom1 in d
                        if f[item.split('_')[0]][item.split('_')[1]][hypercube.split('_')[1]].has_key(dimension.split('_')[1]):
                            f[item.split('_')[0]][item.split('_')[1]][hypercube.split('_')[1]][dimension.split('_')[1]].append(domain.split('_')[1])
                        else:
                            f[item.split('_')[0]][item.split('_')[1]][hypercube.split('_')[1]][dimension.split('_')[1]]=[domain.split('_')[1]]

Actually I am trying to print in this format:

{'t1': {'h1': {'d1': {'dom1': ['a', 'b']}, 'd2': {'dom2': ['a', 'b']}}},
     't2': {'h2': {'d3': {'dom3': ['a', 'b']}}}}

But the output I am getting is:

{'t2': {'h2': {'d3': {'dom3': ['a','b']}}}, 't1': {'h1': {'d2': {'dom2': ['a','b']}}}}

but after changing last thing is in ‘t1’ ‘d1’ value is missing

Answer 1

You don’t want to nest your for loops, you want to nest the for searches as you process each list a, b, c and d, adding deeper and deeper levels to f. This gives your desired output:

f = {}
for item in a:
    ak1,ak2 = item.split('_')
    f[ak1] = {ak2:{}}
for item in b:
    bk1,bk2 = item.split('_')
    next(f[akey][bk1] 
            for akey in f 
                if bk1 in f[akey])[bk2] = {}
for item in c:
    ck1,ck2 = item.split('_')
    next(f[akey][bkey][ck1] 
            for akey in f 
                for bkey in f[akey] 
                    if ck1 in f[akey][bkey])[ck2] = []
for item in d:
    dk1,dk2 = item.split('_')
    next(f[akey][bkey][ckey][dk1] 
            for akey in f 
                for bkey in f[akey]
                    for ckey in f[akey][bkey]
                        if dk1 in f[akey][bkey][ckey]).append(dk2)

import pprint
pprint.pprint(f)

prints:

{'t1': {'h1': {'d1': {'dom1': ['a', 'b']}, 'd2': {'dom2': ['a', 'b']}}},
 't2': {'h2': {'d3': {'dom3': ['a', 'b']}}}}