class MyOwnClass:
# list who contains the queries
queries = []
# a template dict
template_query = {}
template_query['name'] = 'mat'
template_query['age'] = '12'
obj = MyOwnClass()
query = obj.template_query
query['name'] = 'sam'
query['age'] = '23'
obj.queries.append(query)
query2 = obj.template_query
query2['name'] = 'dj'
query2['age'] = '19'
obj.queries.append(query2)
print obj.queries
It gives me
[{'age': '19', 'name': 'dj'}, {'age': '19', 'name': 'dj'}]
while I expect to have
[{'age': '23' , 'name': 'sam'}, {'age': '19', 'name': 'dj'}]
I thought to use a template for this list because I'm gonna to use it very often and there are some default variable who does not need to be changed.
Why does doing it the template_query itself changes? I'm new to python and I'm getting pretty confused.
this is because you are pointing to the same dictionary each time ... and overwriting the keys ...
# query = obj.template_query - dont need this
query = {}
query['name'] = 'sam'
query['age'] = '23'
obj.queries.append(query)
query2 = {} #obj.template_query-dont need this
query2['name'] = 'dj'
query2['age'] = '19'
obj.queries.append(query2)
this should demonstrate your problem
>>> q = {'a':1}
>>> lst = []
>>> lst.append(q)
>>> q['a']=2
>>> lst
[{'a': 2}]
>>> lst.append(q)
>>> lst
[{'a': 2}, {'a': 2}]
you could implement your class differently
class MyOwnClass:
# a template dict
#property
def template_query():
return {'name':'default','age':-1}
this will make obj.template_query return a new dict each time
This is because query and query2 are both referring to the same object. obj.template_query, in this case.
Better to make a template factory:
def template_query(**kwargs):
template = {'name': 'some default value',
'age': 'another default value',
'car': 'generic car name'}
template.update(**kwargs)
return template
That creates a new dictionary every time it's called. So you can do:
>>> my_query = template_query(name="sam")
>>> my_query
{'name': 'sam', 'age': 'another default value', 'car': 'generic car name'}
You're copying the same dict into query2. Instead, you might want to create the needed dict by creating a function template_query() and constructing a new dict each time:
class MyOwnClass:
# a template dict
def template_query():
d = {}
d['name'] = 'mat'
d['age'] = '12'
d['car'] = 'ferrari'
return d
Related
This is my List
List = ['function = function1', 'string = string1', 'hello = hello1', 'new = new1', 'test = test1']
I need to separate the List into two differnt List's sepearted as 'keys' and 'values'
List = ['function = function1', 'string = string1', 'hello = hello1', 'new = new1', 'test = test1']
KeyList
KeyList = ['function', 'string', 'hello', 'new', 'test']
ValueList
ValueList = ['function1', 'string1', 'hello1', 'new1', 'test1']
There are different possible approach. One is the method proposed by Tim, but if you are not familiar with re you could also do:
List = ['function = function1', 'string = string1', 'hello = hello1', 'new = new1', 'test = test1']
KeyList = []
ValueList = []
for item in List:
val = item.split(' = ')
KeyList.append(val[0])
ValueList.append(val[1])
print(KeyList)
print(ValueList)
and the output is:
['function', 'string', 'hello', 'new', 'test']
['function1', 'string1', 'hello1', 'new1', 'test1']
You can simply use split(" = ") and unzip the list of key-value pairs to two tuples:
keys, values = zip(*map(lambda s: s.split(" = "), List))
# keys
# >>> ('function', 'string', 'hello', 'new', 'test')
# values
# >>>('function1', 'string1', 'hello1', 'new1', 'test1')
This is based on the fact that zip(*a_zipped_iterable) works as an unzipping function.
We can use re.findall here:
inp = ['function = function1', 'string = string1', 'hello = hello1', 'new = new1', 'test = test1']
keys = [re.findall(r'(\w+) =', x)[0] for x in inp]
vals = [re.findall(r'\w+ = (\w+)', x)[0] for x in inp]
keys = [pair[0] for pair in pairs]
values = [pair[1] for pair in pairs]
This is my code:
I'm trying to use the following code to insert data into an array of dictionaries but unable to insert properly.
Code:
test_list = {'module_serial-1': 'PSUXA12345680', 'module_name-1': 'CH1.FM5', 'module_name-2': 'CH1.FM6', 'module_serial-2': 'PSUXA12345681'}
def parse_subdevice_modules(row):
modules = []
module = {}
for k, v in row.items():
if v:
if re.match("module_name", k):
module['name'] = v
if re.match("module_serial", k):
module['serial'] = v
modules.append(module)
module = {}
return modules
print(parse_subdevice_modules(test_list))
Expected output:
[{'name':'CH1.FM5', serial': 'PSUXA12345680'}, {'name': 'CH1.FM6', 'serial': 'PSUXA12345681'}]
Actual output:
['serial': 'PSUXA12345680'}, {'name': 'CH1.FM6', 'serial': 'PSUXA12345681'}]
Run it here: https://repl.it/repls/WetSteelblueRange
Please note that the order of the data test_list cannot be altered as it comes via an external API so I used regex. Any ideas would be appreciated.
Your code relies on the wrong assumption that keys are ordered and that the serial will always follow the name. The proper solution here is to use a dict (actually a collections.defaultdict to make things easier) to collect and regroup the values you're interested in based on the module number (the final '-N' in the key). Note that you don't need regexps here - Python string already provide the necessary operations for this task:
from collections import defaultdict
def parse_subdevice_modules(row):
modules = defaultdict(dict)
for k, v in row.items():
# first get rid of what we're not interested in
if not v:
continue
if not k.startswith("module_"):
continue
# retrieve the key number (last char) with
# negative string indexing:
key_num = k[-1]
# retrieve the useful part of the key ("name" or "serial")
# by splitting the string:
key_name = k.split("_")[1].split("-")[0]
# and now we just have to store this in our defaultdict
modules[key_num][key_name] = v
# and return only the values.
# NB: in py2.x you don't need the call to `list`,
# you can just return `modules.values()` directly
modules = list(modules.values())
return modules
test_list = {
'profile': '', 'chassis_name': '123', 'supplier_order_num': '',
'device_type': 'mass_storage', 'device_subtype': 'flashblade',
'module_serial-1': 'PSUXA12345680', 'module_name-1': 'CH1.FM5',
'module_name-2': 'CH1.FM6', 'rack_total_pos': '',
'asset_tag': '002000027493', 'module_serial-2': 'PSUXA12345681',
'purchase_order': '0004530869', 'build': 'Test_Build_for_SNOW',
'po_line_num': '00190', 'mac_address': '', 'position': '7',
'model': 'FB-528TB-10X52.8TB', 'manufacturer': 'PureStorage',
'rack': 'Test_Rack_2', 'serial': 'PMPAM1842147D', 'name': 'FB02'
}
print(parse_subdevice_modules(test_list))
You can do somthing like this also.
test_list = {'module_serial-1': 'PSUXA12345680', 'module_name-1': 'CH1.FM5', 'module_name-2': 'CH1.FM6',
'module_serial-2': 'PSUXA12345681'}
def parse_subdevice_modules(row):
modules_list = []
for key, value in row.items():
if not value or key.startswith('module_name'):
continue
if key.startswith('module_serial'):
module_name_key = f'module_name-{key.split("-")[-1]}'
modules_list.append({'serial': value, 'name': row[module_name_key]})
return modules_list
print(parse_subdevice_modules(test_list))
Output:
[{'serial': 'PSUXA12345680', 'name': 'CH1.FM5'}, {'serial': 'PSUXA12345681', 'name': 'CH1.FM6'}]
You would need to check if module contains 2 elements and append it to modules:
test_list = {'module_serial-1': 'PSUXA12345680', 'module_name-1': 'CH1.FM5', 'module_name-2': 'CH1.FM6', 'module_serial-2': 'PSUXA12345681'}
def parse_subdevice_modules(row):
modules = []
module = {}
for k, v in row.items():
if v:
if k.startswith('module_name'):
module['name'] = v
elif k.startswith("module_serial"):
module['serial'] = v
if len(module) == 2:
modules.append(module)
module = {}
return modules
print(parse_subdevice_modules(test_list))
Returns:
[{'serial': 'PSUXA12345680'}, {'name': 'CH1.FM5'}, {'name': 'CH1.FM6'}, {'serial': 'PSUXA12345681'}]
please help
value = 'http://localhost:8001/issues/load?project_name=react&since=2016-03-24&until=2017-03-25&state=closed&sort=created&direction=asc&per_page=100&labels=Type:%20Bug'
hashing = hash(value)
words = value.split('&')
for data in words:
words2 = data.split('=')
print(words2)
Since words2 has each split into two like:
['http://localhost:8001/issues/load?project_name', 'react']
['since', '2016-03-24']
['until', '2017-03-25']
Use that to add values to a dictionary:
>>> key_vals = {}
>>> for data in words:
... words2 = data.split('=')
... key_vals[words2[0]] = words2[1]
...
>>> pprint.pprint(key_vals)
{'direction': 'asc',
'http://localhost:8001/issues/load?project_name': 'react',
'labels': 'Type:%20Bug',
'per_page': '100',
'since': '2016-03-24',
'sort': 'created',
'state': 'closed',
'until': '2017-03-25'}
And the assignment to key_vals can be reduced to:
key_vals = {key: val for (key, val) in [data.split('=') for data in words]}
I'm struggling with a recursive merge problem.
Let's say I have:
a=[{'name':"bob",
'age':10,
'email':"bob#bla",
'profile':{'id':1, 'role':"admin"}},
{'name':"bob",
'age':10,
'email':"other mail",
'profile':{'id':2, 'role':"dba"},
'home':"/home/bob"
}]
and I need something to recursively merge entries. If value for an existing given key on the same level is different it appends the value to an array.
b = merge(a)
print b
{'name':"bob",
'age':10,
'email':["bob#bla","other mail"],
'profile':{'id':[1,2], 'role'=["admin", "dba"], 'home':"/home/bob"}
I wrote this code:
def merge(items):
merged = {}
for item in items:
for key in item.keys():
if key in merged.keys():
if item[key] != merged[key]:
if not isinstance(merged[key], list):
merged[key] = [merged[key]]
if item[key] not in merged[key]:
merged[key].append(item[key])
else:
merged[key] = item[key]
return merged
The output is:
{'age': 10,
'email': ['bob#bla', 'other mail'],
'home': '/home/bob',
'name': 'bob',
'profile': [{'id': 1, 'role': 'admin'}, {'id': 2, 'role': 'dba'}]}
Which is not what I want.
I can't figure out how to deal with recursion.
Thanks :)
As you iterate over each dictionary in the arguments, then each key and value in each dictionary, you want the following rules:
If there is nothing against that key in the output, add the new key and value to the output;
If there is a value for that key, and it's the same as the new value, do nothing;
If there is a value for that key, and it's a list, append the new value to the list;
If there is a value for that key, and it's a dictionary, recursively merge the new value with the existing dictionary;
If there is a value for that key, and it's neither a list nor a dictionary, make the value in the output a list of the current value and the new value.
In code:
def merge(*dicts):
"""Recursively merge the argument dictionaries."""
out = {}
for dct in dicts:
for key, val in dct.items():
try:
out[key].append(val) # 3.
except AttributeError:
if out[key] == val:
pass # 2.
elif isinstance(out[key], dict):
out[key] = merge(out[key], val) # 4.
else:
out[key] = [out[key], val] # 5.
except KeyError:
out[key] = val # 1.
return out
In use:
>>> import pprint
>>> pprint.pprint(merge(*a))
{'age': 10,
'email': ['bob#bla', 'other mail'],
'home': '/home/bob',
'name': 'bob',
'profile': {'id': [1, 2], 'role': ['admin', 'dba']}}
I know that you can use split() to split a user input into two, but how would you split input that consists of multiple variables ? For example:
User input:
Shawn=14:soccer#2991842
What I would like to do:
name = Shawn
age = 14
course = soccer
idnumber = 2991842
What's the best way to do such thing ?
str = 'Shawn=14:soccer#2991842'
keys = ['name', 'age', 'course', 'idnumber']
values = re.split('[=:#]', str)
print dict(zip(keys, values))
Out[114]: {'age': '14', 'course': 'soccer', 'idnumber': '2991842', 'name': 'Shawn'}
I think Regex will work best here:
>>> from re import split
>>> mystr = "Shawn=14:soccer#2991842"
>>> split("\W", mystr)
['Shawn', '14', 'soccer', '2991842']
>>> lst = split("\W", mystr)
>>> name = lst[0]
>>> name
'Shawn'
>>> age = lst[1]
>>> age
'14'
>>> course = lst[2]
>>> course
'soccer'
>>> idnumber = lst[3]
>>> idnumber
'2991842'
>>>
Also, the above is a step-by-step demonstration. You can actually just do:
name, age, course, idnumber = split("\W", mystr)
Here's how I would do it.
def splitStr(str):
temp = str.split(':')
temp_nameAge = temp[0].split('=')
temp_courseId = temp[1].split('#')
name = temp_nameAge[0]
age = int(temp_nameAge[1])
course = temp_courseId[0]
idnumber = int(temp_courseId[1])
print 'Name = %s, age = %i, course = %s, id_number = %i' % (name, age, course, idnumber)
Another thing you can do is use split like: string.split(":").
Then you can change the format to "name:age:course:number"
You could just keep splitting the splits...
text2split = "Shawn=14:soccer#2991842"
name = text2split.split('=')[0]
age = text2split.split('=')[1].split(':')[0]
course = text2split.split('=')[1].split(':')[1].split('#')[0]
idnumber = text2split.split('=')[1].split(':')[1].split('#')[1]
This isn't the most elegant way to do it, but it'll work so long as text2split always has the same delimeters.
If you are ok with storing them under dictionary keys, you could use named group references
import re
x='shawn=14:soccer#2991842'
re.match(r'(?P<name>.*?)=(?P<age>.*):(?P<course>.*?)#(?P<idnumber>.*)', x).groupdict()
{'idnumber': '2991842', 'course': 'soccer', 'age': '14', 'name': 'shawn