some basic looping through the list of dictionaries and adding the chosen key values to the new dict-CodePudding

Got some basic problems with looping through the list of dictionaries. I want to loop through the list called jslist and get an output as I show at the bottom. Basically I want to extract chosen key: value pairs (the ones I paste as an example below - site_id, sitekey, nickname) from the list and store them in another list of dicts.

jslist = [
    {'site_id': '1111111', 'hostname': 'abc.com', 'nickname': 'abc.com', 'sitekey': '29346385345', 'sitekey_admin': '293857349857934857345', 'timezone': '1', 'visitors_online': '1', 'visitors_today': '34'}, 
    {'site_id': '100992048', 'hostname': 'gcd.com', 'nickname': 'gcd.com', 'sitekey': '938573945739453', 'sitekey_admin': '20395734985793', 'timezone': '1', 'visitors_online': '0', 'visitors_today': '2'}]

dict_1 = {}

for k in jslist:
    dict_1['site_id'] = k['site_id']
    dict_1['sitekey'] = k['sitekey']
    dict_1['nickname'] = k['nickname']


print(list(dict_1))

current output:

{'site_id': '100992048', 'sitekey': '938573945739453', 'nickname': 'gcd.com'}

expected output

[{'site_id': '100992048', 'sitekey': '938573945739453', 'nickname': 'gcd.com'},{'site_id': '1111111', 'sitekey': '29346385345', 'nickname': 'abc.com'}]

CodePudding user response：

You're using one dict for each, so you keep appending the same instance, the dict creation should be inside the loop. Also you can store the needed keys in a list to made the code easier to update and proper

Combining with a list comprehension

keep = {'site_id', 'sitekey', 'nickname'}
jslist_new = [{k: item[k] for k in keep} for item in jslist]

CodePudding user response：

You're just updating the same dict instead of pushing the dict to new list. Here's how:

jslist = [
    {'site_id': '1111111', 'hostname': 'abc.com', 'nickname': 'abc.com', 'sitekey': '29346385345', 'sitekey_admin': '293857349857934857345', 'timezone': '1', 'visitors_online': '1', 'visitors_today': '34'}, 
    {'site_id': '100992048', 'hostname': 'gcd.com', 'nickname': 'gcd.com', 'sitekey': '938573945739453', 'sitekey_admin': '20395734985793', 'timezone': '1', 'visitors_online': '0', 'visitors_today': '2'}]

jslist_new = []

for k in jslist:
    dict_1 = {}
    dict_1['site_id'] = k['site_id']
    dict_1['sitekey'] = k['sitekey']
    dict_1['nickname'] = k['nickname']
    jslist_new.append(dict_1)

print(jslist_new)

CodePudding user response：

You can store the required values in a temporary dictionary and append it to a list... like this

jslist = [
    {'site_id': '1111111', 'hostname': 'abc.com', 'nickname': 'abc.com', 'sitekey': '29346385345', 'sitekey_admin': '293857349857934857345', 'timezone': '1', 'visitors_online': '1', 'visitors_today': '34'}, 
    {'site_id': '100992048', 'hostname': 'gcd.com', 'nickname': 'gcd.com', 'sitekey': '938573945739453', 'sitekey_admin': '20395734985793', 'timezone': '1', 'visitors_online': '0', 'visitors_today': '2'}]

res = []

for dct in jslist:
    temp = dict()

    for key, val in dct.items():
        if key in ("site_id", "sitekey", "nickname"):
            temp[key] = val

    res.append(temp)

print(res)

You can compress it to a list comprehension like this...

jslist = [
    {'site_id': '1111111', 'hostname': 'abc.com', 'nickname': 'abc.com', 'sitekey': '29346385345', 'sitekey_admin': '293857349857934857345', 'timezone': '1', 'visitors_online': '1', 'visitors_today': '34'}, 
    {'site_id': '100992048', 'hostname': 'gcd.com', 'nickname': 'gcd.com', 'sitekey': '938573945739453', 'sitekey_admin': '20395734985793', 'timezone': '1', 'visitors_online': '0', 'visitors_today': '2'}]

res = [{key:val for key, val in dct.items() if key in ("site_id", "sitekey", "nickname")} for dct in jslist]

print(res)