filter a list of dictionarys by key and values & add to the dictionary by specific key-CodePudding

I want to filter a list of dictionarys by key "IP" and value of that key. This is my list for example.

a=[{'IP': '192.168.0.5', 'Temp1': ['58.0']}, 
   {'IP': '192.168.0.6', 'Temp1': ['59.1']}, 
   {'IP': '192.168.0.5', 'Temp2': ['59.1']}, 
   {'IP': '192.168.0.6', 'Temp2': ['60.7']}]

Is it possible to make it look like this?
I want to filter by "IP" so it looks like this:

filtered=[{'IP': '192.168.0.5', 'Temp1': ['58.0'],'Temp2': ['59.1']}, 
          {'IP': '192.168.0.6', 'Temp1': ['59.1'],'Temp2': ['60.7']}]

But I dont know how to exactly do it, can somebody please explain it to me?

CodePudding user response：

This should do it:

        a=[{'IP': '192.168.0.5', 'Temp1': ['58.0']}, 
           {'IP': '192.168.0.6', 'Temp1': ['59.1']}, 
           {'IP': '192.168.0.5', 'Temp2': ['59.1']}, 
           {'IP': '192.168.0.6', 'Temp2': ['60.7']}]        
        filtered=[{'IP': '192.168.0.5', 'Temp1': ['58.0'],'Temp2': ['59.1']}, 
                  {'IP': '192.168.0.6', 'Temp1': ['59.1'],'Temp2': ['60.7']}]        
        
        import collections
        b = collections.defaultdict(dict)
        for d in a:
            for k, v in d.items():
                b[d['IP']][k] = v
        c = list(b.values())
        print(c)

Output is:

[{'IP': '192.168.0.5', 'Temp1': ['58.0'], 'Temp2': ['59.1']}, {'IP': '192.168.0.6', 'Temp1': ['59.1'], 'Temp2': ['60.7']}]

CodePudding user response：

Here's a method where we build the dict of IP: dict via a comprehension before doing the update loop:

>>> a=[{'IP': '192.168.0.5', 'Temp1': ['58.0']},
...    {'IP': '192.168.0.6', 'Temp1': ['59.1']},
...    {'IP': '192.168.0.5', 'Temp2': ['59.1']},
...    {'IP': '192.168.0.6', 'Temp2': ['60.7']}]
>>> by_ip = {ip: {'IP': ip} for ip in {d['IP'] for d in a}}
>>> for d in a:
...     by_ip[d['IP']].update(d)
...
>>> filtered = list(by_ip.values())
>>> filtered
[{'IP': '192.168.0.5', 'Temp1': ['58.0'], 'Temp2': ['59.1']}, {'IP': '192.168.0.6', 'Temp1': ['59.1'], 'Temp2': ['60.7']}]

And here's a method where we can do it in one crazy nested comprehension via functools.reduce:

>>> from functools import reduce
>>> filtered = [reduce(dict.__or__, (d for d in a if d['IP'] == ip), {'IP': ip}) for ip in {d['IP'] for d in a}]
>>> filtered
[{'IP': '192.168.0.5', 'Temp1': ['58.0'], 'Temp2': ['59.1']}, {'IP': '192.168.0.6', 'Temp1': ['59.1'], 'Temp2': ['60.7']}]