I have an array:
["a", "1", "2"]
and a kinda complex dictionary:
{
"a":{
"1": {
"1": "Some text",
"2": "This is the text I want",
"3": "Even more"
},
"2": {
"1": "Some text",
"2": "More text"
}
},
"b": {
"1": "Here is some text",
"2": {
1: "Some text"
},
"3": {}
}
}
How can I use my array, to get "This is the text I want"? I'm new to recursion, so I don't really know how to solve this problem correctly
This should be a bit easier:
keys = ["a", "1", "2"]
dictionary = {
"a":{
"1": {
"1": "Some text",
"2": "This is the text I want",
"3": "Even more"
},
"2": {
"1": "Some text",
"2": "More text"
}
},
"b": {
"1": "Here is some text",
"2": {
1: "Some text"
},
"3": {}
}
}
for key in keys: # drop to lower level of dictionary with each loop
try:
dictionary = dictionary[key]
except KeyError:
dictionary = 'ERROR'
break
print(dictionary) # after the loop ends, 'dictionary' will hold the required value
Since the array is in the correct order, at each recursive step you want to use the front of the list to get the next-most-inner dictionary. Something like this:
def get_dict(arr, d):
if not arr:
return d
return get_dict(arr[1:], d[arr[0]])
A more efficient way would be to reverse the array at the begining, and then take elements from the end, because taking elements from the end is constant time, while taking them from the front is linear (must shift everything over). If you do this, make sure to only reverse it once before the recursion begins.
No need for recursion. A for loop is all you need.
array = ["a", "1", "2"]
data = { ... complex data here ... }
current_data = data
for key in array:
current_data = current_data[key]
print(current_data)
This worked for me:
address = ["a", "1", "2"]
dict_addresses = {
"a": {
"1": {
"1": "Some text",
"2": "This is the text I want",
"3": "Even more"
},
"2": {
"1": "Some text",
"2": "More text"
}
},
"b": {
"1": "Here is some text",
"2": {
1: "Some text"
},
"3": {}
}
}
def recurse(dict_addresses, address, counter=0):
if counter == len(address):
return(dict_addresses)
dict_addresses = dict_addresses[address[counter]]
return(recurse(dict_addresses, address, counter + 1, ))
result = recurse(dict_addresses, address)
print(result)
Output:
This is the text I want
Simple, yet handling missing keys + no recursion
data, path = {...}, ["a", "1", "2"]
while data and path:
data = data.get(path.pop(0))
