PyCharm thinks variable is not used but clearly is inside class method? - python

For some reason PyCharm is telling me that 3 of my 5 list are not used in my function but they in fact are being used in the function and the code completes with the expected results.
This is odd behavior. Is this a bug?
I have seen some issues for f-strings reporting false positives but I do not think this is the same issue here.
def filter_for_vzb_vzt(self, query_results):
vzb_list = []
vzt_list = []
vzt_analyst_tkr = []
vzb_analyst_tkr = []
vzb_lpc_analyst_tkr = []
with open('./Files/{}.json'.format('VZT_ACNA_LIST'), 'r') as df:
vzt_analyst_tkr = json.load(df)
with open('./Files/{}.json'.format('VZB_TAX_ACNA_LIST'), 'r') as df:
vzb_analyst_tkr = json.load(df)
with open('./Files/{}.json'.format('VZB_LPC_ACNA_LIST'), 'r') as df:
vzb_lpc_analyst_tkr = json.load(df)
self.process_vzb_mass(vzb_list, vzb_analyst_tkr, vzb_lpc_analyst_tkr)
self.process_vzt_mass(vzt_list, vzt_analyst_tkr)
self.active_time = False

You are indeed not using those values. Read carefully the message:
local variable <...> value is not used
PyCharm is being very specific - you are assigning these three variables a new list with
<...> = json...
The original empty lists that these variables pointed to are then discarded.
These assignments are not conditional, so you will never use those empty lists - PyCharm is warning you you are not using the empty lists, rather than the variables themselves. You should probably just delete those lines - common practice is to first define variables with values that will actually be used.

Related

Doing calculations while creating a List (in Python)

I'm getting data from an API and storing it on Python dictionary (and then a list of dictionaries).
I need to do calculations (max, sum, divisions...) on the dictionary data to create extra data to add to the same dictionary/list.
My current code looks like this:
stream = whatever (whatever, whatever)
keywords = []
for batch in stream:
for row in batch.results:
max_clicks = max(data_keywords["keywords_clicks"])
weighted_clicks = sum(data_keywords["keywords_weighted"])/sum(data_keywords["keywords_clicks"])
data_keywords = {}
data_keywords["keywords_text"] = row.ad_group_criterion.keyword.text
data_keywords["keywords_clicks"] = row.metrics.clicks
data_keywords["keywords_conversion_rate"] = row.metrics.conversions_from_interactions_rate
data_keywords["keywords_weighted"] = row.metrics.clicks * row.metrics.conversions_from_interactions_rate
data_keywords["etv"] = (data_keywords["keywords_clicks"]/max_clicks*data_keywords["keywords_conversion_rate"])+((1-data_keywords["keywords_clicks"]/max_clicks)*weighted_clicks)
keywords.append(data_keywords)
This doesn't work, it gives UnboundLocalError (local variable 'data_keywords' referenced before assignment). I've tried different options and got different errors.
data_keywords["etv"] is what I want to calculate ("max_clicks", "weighted_clicks" and data_keywords["keywords_weighted"] are intermediate calculations for that)
The main problem is that I need to calculate max and sum for all values inside the dictionary, then do a calculation using that max and sum for each value and then store the results in the dictionary itself.
So I don't know where to put the code to do the calculations (before the dictionary, inside the dictionary, after the dictionary or a mix)
I guess it should be possible, but I'm a Python/programming newbie and can't figure this out.
It's probably not relevant, but in case you are wondering, I'm trying to create a weighted sort (https://moz.com/blog/build-your-own-weighted-sort). And I can't use models/database to store data.
Thanks!
EDIT: Some extra info, in case it helps understand better what I need: The results that the keywords list gives without the calculations is something like this:
[{'keywords_text': 'whatever', 'keywords_clicks': 5, 'keywords_conversion_rate': 6.3}, {'keywords_text': 'whatever2', 'keywords_clicks': 50, 'keywords_conversion_rate': 2.3}, {'keywords_text': 'whatever3', 'keywords_clicks': 20, 'keywords_conversion_rate': 2.0}]
I want basically to add to this keywords list a new key/value of 'etv': 8.5 or whatever for each keyword. That etv should come from the formula that I put on my code (data_keywords["etv"] = ...) but maybe it needs changes to work in Python.
The info from this "original" keywords list comes directly from the API (I don't have that data stored anywhere) and it works perfectly if I just request the info and store it in that list. But when the problems come when I introduce the calculations (specially using sum and max inside a loop I guess).
The UnboundLocalError is because you are trying to access data_keywords["keywords_clicks"] before you have declared data_keywords or set the value for "keywords_clicks".
Also, I think you need to be clearer about what data structure you are trying to create. You mention "a list of dictionaries" which I don't see. Maybe you are trying to create a dictionary of lists, but it looks like you overwrite the dictionary values each time you go through your loop.
adding my response as an answer, as I do not have enough reputation to comment
To get rid of assignment error just move the line data_keywords = {} above max_clicks = max(data_keywords["keywords_clicks"])
Here you are trying to access a local variable before its declaration. The code in this case is trying to access a global variable which doesn't seems to exist.
stream = whatever (whatever, whatever)
keywords = []
for batch in stream:
for row in batch.results:
data_keywords = {}
max_clicks = max(data_keywords["keywords_clicks"])
weighted_clicks = sum(data_keywords["keywords_weighted"])/sum(data_keywords["keywords_clicks"])
data_keywords["keywords_text"] = row.ad_group_criterion.keyword.text
data_keywords["keywords_clicks"] = row.metrics.clicks
data_keywords["keywords_conversion_rate"] = row.metrics.conversions_from_interactions_rate
data_keywords["keywords_weighted"] = row.metrics.clicks * row.metrics.conversions_from_interactions_rate
data_keywords["etv"] = (data_keywords["keywords_clicks"]/max_clicks*data_keywords["keywords_conversion_rate"])+((1-data_keywords["keywords_clicks"]/max_clicks)*weighted_clicks)
keywords.append(data_keywords)
More on that here
You can't refer to elements of the dictionary before you create it. Move those variable assignments down to after you assign the dictionary elements.
for batch in stream:
for row in batch.results:
data_keywords = {}
data_keywords["keywords_text"] = row.ad_group_criterion.keyword.text
data_keywords["keywords_clicks"] = row.metrics.clicks
data_keywords["keywords_conversion_rate"] = row.metrics.conversions_from_interactions_rate
data_keywords["keywords_weighted"] = row.metrics.clicks * row.metrics.conversions_from_interactions_rate
max_clicks = max(data_keywords["keywords_clicks"])
weighted_clicks = sum(data_keywords["keywords_weighted"])/sum(data_keywords["keywords_clicks"])
data_keywords["etv"] = (data_keywords["keywords_clicks"]/max_clicks*data_keywords["keywords_conversion_rate"])+((1-data_keywords["keywords_clicks"]/max_clicks)*weighted_clicks)
keywords.append(data_keywords)

Calling existing variable (list) reconstructed with StringVar()

I have a several lists that I am trying to activate or use that are named as follows:
public_forum_jr_soc = []
parliamentary_jr_soc = []
european_jr_soc = []
etc...
I have a bunch of radiobuttons that has variables to recreate these lists names, and it outputs something like this.
print(self.select_league.get()+self.select_age.get()+self.select_grade.get())
append_name = self.select_league.get()+self.select_age.get()+self.select_grade.get()
>>>
european_jr_soc
I try to proceed to use this list in as an argument for a function.
output_data(append_name)
def master_groper2(outof48):
for i in outof48:
if i[15] in ['ENGLISH','english','']:
i[15] = 'English'
elif i[15] in ['Mandarin','CHINESE',]:
i[15] = 'Chinese'
However, I get a IndexError: string index out of range as python reads it as european_jr_soc, instead of the actual list, despite sharing the same name, how could I have python have it read it as the variable list?

Change part of csv string panda

I would like to change the word consolidation (two times in the following string) with an other value with a variable or ? (ex. breakout/outofconsolidation/inside)
Can I help me to achieve this, please?
dfconsolidationcsv.to_csv(r'symbols\stocks_consolidation_sp500.csv', index = False)
a = ('breakout')
df{a}csv.to_csv(r'symbols\stocks_{a}_sp500.csv', index = False)
Unless there is a justifiable reason to be creating dynamic variable assignments, I would avoid doing so. In this case, defining your DataFrame variables in a dict is probably sufficient:
# store df in a dict instead of separate variables
df_dict = dict()
df_dict['consolidation'] = dfconslidationcv
df_dict['breakout'] = dfbreakoutcv
...
# invoke command for a specific variable
a = 'breakout'
df_dict[a].to_csv(r'symbols\stocks_%s_sp500.csv' % a, index = False)
Now, if there is an overwhelming reason why you HAVE to use pre-existing variable names that need to be changed dynamically, I think you can do something like this:
a = 'breakout'
exec("df%scsv.to_csv(r'symbols\stocks_%s_sp500.csv', index=False)" % (a, a))

Python: Running function to append values to an empty list returns no values

This is probably a very basic question but I haven't been able to figure this out.
I'm currently using the following to append values to an empty list
shoes = {'groups':['running','walking']}
df_shoes_group_names = pd.DataFrame(shoes)
shoes_group_name=[]
for type in df_shoes_group_names['groups']:
shoes_group_name.append(type)
shoes_group_name
['running', 'walking']
I'm trying to accomplish the same using a for loop, however, when I execute the loop the list comes back as blank
shoes_group_name=[]
def list_builder(dataframe_name):
if 'shoes' in dataframe_name:
for type in df_shoes_group_names['groups']:
shoes_group_name.append(type)
list_builder(df_shoes_group_names)
shoes_group_name
[]
Reason for the function is that eventually I'll have multiple DF's with different product's so i'd like to just have if statements within the function to handle the creation of each list
so for example future examples could look like this:
df_shoes_group_names
df_boots_group_names
df_sandals_group_names
shoes_group_name=[]
boots_group_name=[]
sandals_group_name=[]
def list_builder(dataframe_name):
if 'shoes' in dataframe_name:
for type in df_shoes_group_names['groups']:
shoes_group_name.append(type)
elif 'boots' in dataframe_name:
for type in df_boots_group_names['groups']:
boots_group_name.append(type)
elif 'sandals' in dataframe_name:
for type in df_sandals_group_names['groups']:
sandals_group_name.append(type)
list_builder(df_shoes_group_names)
list_builder(df_boots_group_names)
list_builder(df_sandals_group_names)
Not sure if I'm approaching this the right way so any advice would be appreciated.
Best,
You should never call or search a variable name as if it were a string.
Instead, use a dictionary to store a variable number of variables.
Bad practice
# dataframes
df_shoes_group_names = pd.DataFrame(...)
df_boots_group_names = pd.DataFrame(...)
df_sandals_group_names = pd.DataFrame(...)
def foo(x):
if shoes in df_shoes_group_names: # <-- THIS WILL NOT WORK
# do something with x
Good practice
# dataframes
df_shoes_group_names = pd.DataFrame(...)
df_boots_group_names = pd.DataFrame(...)
df_sandals_group_names = pd.DataFrame(...)
dfs = {'shoes': df_shoes_group_names,
'boots': df_boots_group_names,
'sandals': df_sandals_group_names}
def foo(key):
if 'shoes' in key: # <-- THIS WILL WORK
# do something with dfs[key]

Python - efficient way to create 20 variables?

I need to create 20 variables in Python. That variables are all needed, they should initially be empty strings and the empty strings will later be replaced with other strings. I cann not create the variables as needed when they are needed because I also have some if/else statements that need to check whether the variables are still empty or already equal to other strings.
Instead of writing
variable_a = ''
variable_b = ''
....
I thought at something like
list = ['a', 'b']
for item in list:
exec("'variable_'+item+' = '''")
This code does not lead to an error, but still is does not do what I would expect - the variables are not created with the names "variable_1" and so on.
Where is my mistake?
Thanks, Woodpicker
Where is my mistake?
There are possibly three mistakes. The first is that 'variable_' + 'a' obviously isn't equal to 'variable_1'. The second is the quoting in the argument to exec. Do
for x in list:
exec("variable_%s = ''" % x)
to get variable_a etc.
The third mistake is that you're not using a list or dict for this. Just do
variable = dict((x, '') for x in list)
then get the contents of "variable" a with variable['a']. Don't fight the language. Use it.
I have the same question as others (of not using a list or hash), but if you need , you can try this:
for i in xrange(1,20):
locals()['variable_%s' %i] = ''
Im assuming you would just need this in the local scope. Refer to the manual for more information on locals
never used it, but something like this may work:
liste = ['a', 'b']
for item in liste:
locals()[item] = ''

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