I have the following dictionary (It is for creating json),
temp = {'logs':[]}
I want to append dictionaries, but i only got 1 key:val at a time.
what I tried:
temp['logs'].append({key:val})
This does as expected and appends the dict to the array.
But now I want to add a key/val pair to this dictionary, how can I do this?
I've tried using append/extend but that just adds a new dictionary to the list.
But now I want to add a key/val pair to this dictionary
You can index the list and update that dictionary:
temp['logs'][0].update({'new_key': 'new_value'})
You can use this command to change your dict values :
>>> temp['logs'][0]={'no':'val'}
>>> temp
{'logs': [{'no': 'val'}]}
And this one to add values :
>>> temp['logs'][0].update({'yes':'val'})
>>> temp
{'logs': [{'key': 'val', 'yes': 'val'}]}
There must be unique "key" every time you append it. (If it is for json)
Also making "=" will update your old dictionary
What I have done when I was stuck once is
user = {}
name,password,id1 = [],[],[]
user1=session.query(User).all()
for i in user1:
name=i.name
password=i.password
id1=i.id
user.update({ id1:{
"name" : name,
"password" : password,
}
})
check this link might be helpful to you
How to convert List of JSON frames to JSON frame
Note that adding a dictionary (or any object) to a list only stores a reference, not a copy.
You can therefor do this:
>>> temp = {'logs': []}
>>> log_entry = {'key1': 'val1'}
>>> temp['logs'].append(log_entry)
>>> temp
{'logs': [{'key1': 'val1'}]}
>>> log_entry['key2'] = 'val2'
>>> temp
{'logs': [{'key2': 'val2', 'key1': 'val1'}]}
However, you might be able to circumvent to whole issue by using dict comprehension (only in Python >=2.7)
>>> temp = {'logs': [{key: value for key, value in my_generator}]
Try this example:
temp = {
'logs':[]
}
[temp['logs'].append(log) for log in errors['logs']]
Your log data would be list with multiple dictionary
Related
#Input
dict_1 = {"conn": {"ts":15,"uid":"ABC","orig_h":"10.10.210.250"}}
dict_2 = {"conn": {"ts":15,"uid":"ABC","orig_h":"10.10.210.252"}}
#Mapper can be modified as required
mapper = {"10.10.210.250":"black","192.168.2.1":"black"}
I am getting each dict in a loop, in each iteration I need to check a dict against the mapper and append a flag based on match between dict_1.orig_h and mapper.10.10.210.250 . I have the flexibility to define the mapper however I need.
So the desired result would be:
dict_1 = {"conn": {"ts":15,"uid":"ABC","orig_h":"10.10.210.250", "class":"black"}}
dict_2 will remain unchanged since there is no matching value in mapper.
This is kinda what I want, but it works only if orig_h is an int
import collections
result = collections.defaultdict(dict)
for d in dict_1:
result[d[int('orig_h')]].update(d)
for d in mapper:
result[d[int('orig_h')]].update(d)
Not much explaining to be done; if the ip is in the mapper dictionary (if mapper has a key which is that ip) then set the desired attribute of the dict to the value of the key in the mapper dict ('black' here).
def update_dict(dic, mapper):
ip = dic['conn']['orig_h']
if ip in mapper:
dic['conn']['class'] = mapper[ip]
which works exactly as desired:
>>> update_dict(dict_1, mapper)
>>> dict_1
{'conn': {'ts': 15, 'uid': 'ABC', 'orig_h': '10.10.210.250', 'class': 'black'}}
>>> update_dict(dict_2, mapper)
>>> dict_2
{'conn': {'ts': 15, 'uid': 'ABC', 'orig_h': '10.10.210.252'}}
Extracting the conn value for simplicity:
conn_data = dict_1['conn']
conn_data['class'] = mapper[conn_data['orig_h']]
A two liner, extracting class and dict if the 'orig_h' is in the mapper dictionary's keys, if it id, keep it, otherwise don't keep it, then create a new dictionary comprehension inside the list comprehension to add 'class' to the dictionary's 'conn' key's dictionary.
l=[(i,mapper[i['conn']['orig_h']]) for i in (dict_1,dict_2) if i['conn']['orig_h'] in mapper]
print([{'conn':dict(a['conn'],**{'class':b})} for a,b in l])
BTW this answer chooses the dictionaries automatically
I have an embedded dictionary created as:
all_stats = {}
all_stats['user1'] = {}
I first add an entry with:
all_stats['stat0'] = 1
I then have a dictionary of each additional entries that will be added to all_stats for that user:
user_stats = {'stat1':5, 'stat2':3}
How can I add these to the embedded dictionary, so I end up with:
print(all_stats)
{'user1': {'stat0:1', 'stat1':5, 'stat2':3}}
I've tried:
all_stats['user1'].update(k=v for k,v in user_stats.items())
but this throws a SyntaxError
You don't need the for loop; you can update one dictionary with another dictionary directly:
all_stats['user1']['stat0'] = 1
all_stats['user1'].update(user_stats)
all_stats
# {'user1': {'stat0': 1, 'stat1': 5, 'stat2': 3}}
As for the Syntax Error, as commented by #idjaw, you can't use k=v in a comprehension in the way you've used; Something similar but acceptable would be:
all_stats['user1'].update({k:v for k,v in user_stats.items()})
So i have following dict:
my_dict{'key1': 'value1',
'key2': 'value2',
'key3': json.dumps([
{"**subkey1**": "subvalue1", "**subkey2**": "subvalue2",},
{"**subkey1**": "other_subvalue", "**subkey2**":"other_subvalue2"}])
}
What I need is to somehow made a def where i have to check and for each subkey2 to change its value only for the def itself
And all subkey1 to check if its value is the same like the second subkey1
Please note I am talking about only subkey1 which I have twice.
I don't want to set them manually. Mean I have this dict global, and calling it from many def, so i need to make these changes and check inside each def
What I tried is:
def recurse_keys(my_dict, indent = ''):
print(indent+str(key))
if isinstance(my_dict[key], dict):
recurse_keys(my_dict[key], indent+' ')
recurse_keys(my_dict)
And for now it is only printing all of my params, but am not sure how to proceed
Example:
my_dict{'name': 'georgi',
'famili': 'ivanov',
'drinks': json.dumps([
{"breakfast": "milk", "lunch": "beer",},
{"breakfast": "tea", "lunch":"vodka"}])
def test()
....check if both breakfast are the same and if not make them so....(all these, mean dict and the function it self are in same file)
so I need to check if the values for the two breakfast are the same (without to know them) and if they are not, to make them so.
And also to check if there is lunch with empty value or 0 and again if not, to make it so
If you want to edit a json string, then probably the easiest way is to decode it to python data types d = json.loads(str), edit it, then encode it back to string str = json.dumps(d) (python JSON).
import json
my_dict = {'name': 'georgi',\
'famili': 'ivanov',\
'drinks': json.dumps([\
{"breakfast": "milk", "lunch": "beer",},\
{"breakfast": "tea", "lunch":"vodka"}])};
ddict = json.loads(my_dict["drinks"]) # json str to python data types
seen = {}; # store the items already seen
# for each dictionary object in key3
for d in range(0,len(ddict)):
for k in ddict[d]:
if k in seen:
# update the value to the one already seen
ddict[d][k] = seen[k];
if k == "lunch" and (ddict[d] == "" or ddict[d] is None):
ddict[d] = alternative_lunch_value;
else:
seen[k] = ddict[d][k];
my_dict["drinks"] = json.dumps(ddict);
print(my_dict);
The result on my machine is:
{'drinks': '[{"breakfast": "milk", "lunch": "beer"}, {"breakfast": "milk", "lunch": "beer"}]',
'famili': 'ivanov',
'name': 'georgi'}
Updating dict values
Because you wanted to update the values in my_dict so that it can be read by other modules, rather than just read the values. If all you wanted to do was read the values, then you can iterate over the list ddict as follows:
for value in ddict:
print("Sub1:{0} Sub2:{1}\n".format(value["**subkey1**"], value["**subkey2**"]));
However, since you want to update the values in the existing list, then you will need to iterate over a list of the indexes. As shown below...
Range() and len()
Range(start,end) gives a list with values from start to end. So a = range(1,4) assigns [1,2,3,4] to a. Also len(a) will return the number of items in the list, so 4 in this case. Using these principals, you can iterate through your ddict.
for d in range(1,len(ddict):
ddict[d]["**subkey1**"] = new_value;
Hope this helps get you started. If you update your question with more details on exactly what you want (i.e. example input and output, perhaps psudo code), then we will be able to give you a better answer.
I was attempting to add an attribute to a pre-existing object in a dictionary:
key = 'key1'
dictObj = {}
dictObj[key] = "hello world!"
#attempt 236 (j/k)
dictObj[key]["property2"] = "value2" ###'str' object does not support item assignment
#another attempt
setattr(dictObj[key], 'property2', 'value2') ###'dict' object has no attribute 'property2'
#successful attempt that I did not like
dictObj[key] = {'property':'value', 'property2':''} ###instantiating the dict object with all properties defined seemed wrong...
#this did allow for the following to work
dictObj[key]["property2"] = "value2"
I tried various combinations (including setattr, etc.) and was not having much luck.
Once I have added an item to a Dictionary, how can I add additional key/value pairs to that item (not add another item to the dictionary).
As I was writing up this question, I realized my mistake.
key = 'key1'
dictObj = {}
dictObj[key] = {} #here is where the mistake was
dictObj[key]["property2"] = "value2"
The problem appears to be that I was instantiating the object with key 'key1' as a string instead of a dictionary. As such, I was not able to add a key to a string. This was one of many issues I encountered while trying to figure out this simple problem. I encountered KeyErrors as well when I varied the code a bit.
Strictly reading the question, we are considering adding an attribute to the object. This can look like this:
class DictObj(dict):
pass
dictObj = DictObj(dict)
dictObj.key = {'property2': 'value2'}
And then, we can use dictObj.key == {'property2': 'value2'}
Given the context of the question, we are dealing with adding a property to the dictionary. This can be done (in addition to #John Bartels's approach) in the following ways:
1st option - add the "full" content in one line:
dictObj = {'key': {'property2': 'value2'}}
2nd option for the case of dictionary creation with initial values:
dictObj = dict(key = dict(property2 = 'value2'))
3rd option (Python 3.5 and higher):
dictObj = {}
dictObj2 = {'key': {'property2': 'value2'}}
dictObj = {**dictObj, **dictObj2}
4th option (Python 3.9 and higher):
dictObj = {}
dictObj |= {'key': {'property2': 'value2'}}
In all cases the result will be: dictObj == {'key': {'property2': 'value2'}}
I was wondering if there was a way to initialize a dictionary in python with keys but no corresponding values until I set them. Such as:
Definition = {'apple': , 'ball': }
and then later i can set them:
Definition[key] = something
I only want to initialize keys but I don't know the corresponding values until I have to set them later. Basically I know what keys I want to add the values as they are found. Thanks.
Use the fromkeys function to initialize a dictionary with any default value. In your case, you will initialize with None since you don't have a default value in mind.
empty_dict = dict.fromkeys(['apple','ball'])
this will initialize empty_dict as:
empty_dict = {'apple': None, 'ball': None}
As an alternative, if you wanted to initialize the dictionary with some default value other than None, you can do:
default_value = 'xyz'
nonempty_dict = dict.fromkeys(['apple','ball'],default_value)
You could initialize them to None.
you could use a defaultdict. It will let you set dictionary values without worrying if the key already exists. If you access a key that has not been initialized yet it will return a value you specify (in the below example it will return None)
from collections import defaultdict
your_dict = defaultdict(lambda : None)
It would be good to know what your purpose is, why you want to initialize the keys in the first place. I am not sure you need to do that at all.
1) If you want to count the number of occurrences of keys, you can just do:
Definition = {}
# ...
Definition[key] = Definition.get(key, 0) + 1
2) If you want to get None (or some other value) later for keys that you did not encounter, again you can just use the get() method:
Definition.get(key) # returns None if key not stored
Definition.get(key, default_other_than_none)
3) For all other purposes, you can just use a list of the expected keys, and check if the keys found later match those.
For example, if you only want to store values for those keys:
expected_keys = ['apple', 'banana']
# ...
if key_found in expected_keys:
Definition[key_found] = value
Or if you want to make sure all expected keys were found:
assert(all(key in Definition for key in expected_keys))
You can initialize the values as empty strings and fill them in later as they are found.
dictionary = {'one':'','two':''}
dictionary['one']=1
dictionary['two']=2
Comprehension could be also convenient in this case:
# from a list
keys = ["k1", "k2"]
d = {k:None for k in keys}
# or from another dict
d1 = {"k1" : 1, "k2" : 2}
d2 = {k:None for k in d1.keys()}
d2
# {'k1': None, 'k2': None}
q = input("Apple")
w = input("Ball")
Definition = {'apple': q, 'ball': w}
Based on the clarifying comment by #user2989027, I think a good solution is the following:
definition = ['apple', 'ball']
data = {'orange':1, 'pear':2, 'apple':3, 'ball':4}
my_data = {}
for k in definition:
try:
my_data[k]=data[k]
except KeyError:
pass
print my_data
I tried not to do anything fancy here. I setup my data and an empty dictionary. I then loop through a list of strings that represent potential keys in my data dictionary. I copy each value from data to my_data, but consider the case where data may not have the key that I want.