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How to concatenate a series to a pandas dataframe in python?

I would like to iterate through a dataframe rows and concatenate that row to a different dataframe basically building up a different dataframe with some rows.
For example:
`IPCSection and IPCClass Dataframes
allcolumns = np.concatenate((IPCSection.columns, IPCClass.columns), axis = 0)
finalpatentclasses = pd.DataFrame(columns=allcolumns)
for isec, secrow in IPCSection.iterrows():
for icl, clrow in IPCClass.iterrows():
if (secrow[0] in clrow[0]):
pdList = [finalpatentclasses, pd.DataFrame(secrow), pd.DataFrame(clrow)]
finalpatentclasses = pd.concat(pdList, axis=0, ignore_index=True)
display(finalpatentclasses)
The output is:
I want the nan values to dissapear and move all the data under the correct columns. I tried axis = 1 but messes up the column names. Append does not work as well all values are placed diagonally at the table with nan values as well.

Alright, I have figured it out. The idea is that you create a newrowDataframe and concatenate all the data in a list from there you can add it to the dataframe and then conc with the final dataframe.
Here is the code:
allcolumns = np.concatenate((IPCSection.columns, IPCClass.columns), axis = 0)
finalpatentclasses = pd.DataFrame(columns=allcolumns)
for isec, secrow in IPCSection.iterrows():
for icl, clrow in IPCClass.iterrows():
newrow = pd.DataFrame(columns=allcolumns)
values = np.concatenate((secrow.values, subclrow.values), axis=0)
newrow.loc[len(newrow.index)] = values
finalpatentclasses = pd.concat([finalpatentclasses, newrow], axis=0)
finalpatentclasses.reset_index(drop=false, inplace=True)
display(finalpatentclasses)
Update the code below is more efficient:
allcolumns = np.concatenate((IPCSection.columns, IPCClass.columns, IPCSubClass.columns, IPCGroup.columns), axis = 0)
newList = []
for secrow in IPCSection.itertuples():
for clrow in IPCClass.itertuples():
if (secrow[1] in clrow[1]):
values = ([secrow[1], secrow[2], subclrow[1], subclrow[2]])
new_row = {IPCSection.columns[0]: [secrow[1]], IPCSection.columns[1]: [secrow[2]],
IPCClass.columns[0]: [clrow[1]], IPCClass.columns[1]: [clrow[2]]}
newList.append(values)
finalpatentclasses = pd.DataFrame(newList, columns=allcolumns)
display(finalpatentclasses)

populate column in dataframe with a list using for loop

I would like to populate a dataframe using a for loop.
one of the column is a list.
this list is empty at the begining at each itteration an element is added or removed from it.
when I print my list at each iteration I am getting the right results, but when I print my dataframe, I am getting the same list on each row:
I you have a look to my code the list I am updatin is list_employe. The magic should happen in the 3 last rows but it did not.
Does anyone have an idea why the list is updated in one way and the dataframe record only the last update on all rows
list_employe = []
total_employe = 0
rows=[]
shiftday = example['SHIFT_DATE'].dt.strftime('%Y-%m-%d').unique().tolist()
for i in shiftday:
shift_day = example[example['SHIFT_DATE'] == i]
list_employe_shift = example[example['SHIFT_DATE']==i]['EMPLOYEE_CODE_POS_UPPER'].unique().tolist()
new_employe = 0
end_employe = 0
for k in list_employe_shift:
shift_days_emp = shift_day[shift_day['EMPLOYEE_CODE_POS_UPPER'] == k]
days = shift_days_emp.iloc[0]['last_day']
#print(days)
if k in list_employe:
if days>1:
end_employe= end_employe+1
total_employe = total_employe-1
list_employe.remove(k)
else:
new_employe = new_employe+1
total_employe = total_employe + 1
list_employe.extend([k])
day = i
total_emp = total_employe
new_emp = new_employe
end_emp = end_employe
rows.append([day, total_emp, new_emp, end_emp, list_employe])
print(list_employe)
df = pd.DataFrame(rows, columns=["day", "total_employe", "new_employe", "end_employe", "list_employe"])

the list list_employe is always the same object that you append to the list rows. What you need to do to solve the problem is at the 3rd line from the bottom : rows.append([day, total_emp, new_emp, end_emp, list(list_employe)]) Which create a new list at each itteration

pandas: while loop to simultaneously advance through multiple lists and call functions

I want my code to:
read data from a CSV and make a dataframe: "source_df"
see if the dataframe contains any columns specified in a list:
"possible_columns"
call a unique function to replace the values in each column whose header is found in the "possible_columns" the list, then insert the modified values in a new dataframe: "destination_df"
Here it is:
import pandas as pd
#creates source_df
file = "yes-no-true-false.csv"
data = pd.read_csv(file)
source_df = pd.DataFrame(data)
#creates destination_df
blanklist = []
destination_df = pd.DataFrame(blanklist)
#create the column header lists for comparison in the while loop
columns = source_df.head(0)
possible_columns = ['yes/no','true/false']
#establish the functions list and define the functions to replace column values
fix_functions_list = ['yes_no_fix()','true_false_fix()']
def yes_no_fix():
destination_df['yes/no'] = destination_df['yes/no fixed'].replace("No","0").replace("Yes","1")
def true_false_fix():
destination_df['true/false'] = destination_df['true/false fixed'].replace('False', '1').replace('True', '0')
'''use the counter to call a unique function from the function list to replace the values in each column whose header is found in the "possible_columns" the list, insert the modified values in "destination_df, then advance the counter'''
counter = 0
while counter < len(possible_columns):
if possible_columns[counter] in columns:
destination_df.insert(counter, possible_columns[counter], source_df[possible_columns[counter]])
fix_functions_list[counter]
counter = counter + 1
#see if it works
print(destination_df.head(10))
When I print(destination_df), I see the unmodified column values from source_df. When I call the functions independently they work, which makes me think something is going wrong in my while loop.

Your issue is that you are trying to call a function that is stored in a list as a string.
fix_functions_list[cnt]
This will not actually run the function just access the string value.
I would try and find another way to run these functions.

def yes_no_fix():
destination_df['yes/no'] = destination_df['yes/no fixed'].replace("No","0").replace("Yes","1")
def true_false_fix():
destination_df['true/false'] = destination_df['true/false fixed'].replace('False', '1').replace('True', '0')
fix_functions_list = {0:yes_no_fix,1:true_false_fix}
and change the function calling to like below
fix_functions_list[counter]()

#creates source_df
file = "yes-no-true-false.csv"
data = pd.read_csv(file)
source_df = pd.DataFrame(data)
possible_columns = ['yes/no','true/false']
mapping_dict={'yes/no':{"No":"0","Yes":"1"} ,'true/false': {'False':'1','True': '0'}
old_columns=[if column not in possible_columns for column in source_df.columns]
existed_columns=[if column in possible_columns for column in source_df.columns]
new_df=source_df[existed_columns]
for column in new_df.columns:
new_df[column].map(mapping_dict[column])
new_df[old_columns]=source_df[old_columns]

How to compare two str values dataframe python pandas

I am trying to compare two different values in a dataframe. The questions/answers I've found I wasn't able to utilize.
import pandas as pd
# from datetime import timedelta
"""
read csv file
clean date column
convert date str to datetime
sort for equity options
replace date str column with datetime column
"""
trade_reader = pd.read_csv('TastyTrades.csv')
trade_reader['Date'] = trade_reader['Date'].replace({'T': ' ', '-0500': ''}, regex=True)
date_converter = pd.to_datetime(trade_reader['Date'], format="%Y-%m-%d %H:%M:%S")
options_frame = trade_reader.loc[(trade_reader['Instrument Type'] == 'Equity Option')]
clean_frame = options_frame.replace(to_replace=['Date'], value='date_converter')
# Separate opening transaction from closing transactions, combine frames
opens = clean_frame[clean_frame['Action'].isin(['BUY_TO_OPEN', 'SELL_TO_OPEN'])]
closes = clean_frame[clean_frame['Action'].isin(['BUY_TO_CLOSE', 'SELL_TO_CLOSE'])]
open_close_set = set(opens['Symbol']) & set(closes['Symbol'])
open_close_frame = clean_frame[clean_frame['Symbol'].isin(open_close_set)]
'''
convert Value to float
sort for trade readability
write
'''
ocf_float = open_close_frame['Value'].astype(float)
ocf_sorted = open_close_frame.sort_values(by=['Date', 'Call or Put'], ascending=True)
# for readability, revert back to ocf_sorted below
ocf_list = ocf_sorted.drop(
['Type', 'Instrument Type', 'Description', 'Quantity', 'Average Price', 'Commissions', 'Fees', 'Multiplier'], axis=1
)
ocf_list.reset_index(drop=True, inplace=True)
ocf_list['Strategy'] = ''
# ocf_list.to_csv('Sorted.csv')
# create strategy list
debit_single = []
debit_vertical = []
debit_calendar = []
credit_vertical = []
iron_condor = []
# shift columns
ocf_list['Symbol Shift'] = ocf_list['Underlying Symbol'].shift(1)
ocf_list['Symbol Check'] = ocf_list['Underlying Symbol'] == ocf_list['Symbol Shift']
# compare symbols, append depending on criteria met
for row in ocf_list:
if row['Symbol Shift'] is row['Underlying Symbol']:
debit_vertical.append(row)
print(type(ocf_list['Underlying Symbol']))
ocf_list.to_csv('Sorted.csv')
print(debit_vertical)
# delta = timedelta(seconds=10)
The error I get is:
line 51, in <module>
if row['Symbol Check'][-1] is row['Underlying Symbol'][-1]:
TypeError: string indices must be integers
I am trying to compare the newly created shifted column to the original, and if they are the same, append to a list. Is there a way to compare two string values at all in python? I've tried checking if Symbol Check is true and it still returns an error about str indices must be int. .iterrows() didn't work

Here, you will actually iterate through the columns of your DataFrame, not the rows:
for row in ocf_list:
if row['Symbol Shift'] is row['Underlying Symbol']:
debit_vertical.append(row)
You can use one of the methods iterrows or itertuples to iterate through the rows, but they return rows as lists and tuples respectively, which means you can't index them using the column names, as you did here.
Second, you should use == instead of is since you are probably comparing values, not identities.
Lastly, I would skip iterating over the rows entirely, as pandas is made for selecting rows based on a condition. You should be able to replace the aforementioned code with this:
debit_vertical = ocf_list[ocf_list['Symbol Shift'] == ocf_list['Underlying Symbol']].values.tolist()

Iterating over multiple pandas dataframe is slow

I'm trying to find the number of similar words for all rows in Dataframe1 for every single row with words in Dataframe 2.
Based on the similarities I want to create a new data frame with where columns = N rows of dataframe2
values = similarity.
My current code is working, but it runs very slow. I'm not sure how to optimize it...
df = pd.DataFrame([])
for x in range(10000):
save = {}
terms_1 = data['text_tokenized'].iloc[x]
save['code'] = data['code'].iloc[x]
for y in range(3000):
terms_2 = data2['terms'].iloc[y]
similar_n = len(list(terms_2.intersection(terms_1)))
save[data2['code'].iloc[y]] = similar_n
df = df.append(pd.DataFrame([save]))
Update: new code (still running slow)
def get_sim(x, terms):
similar_n = len(list(x.intersection(terms)))
return similar_n
for index in icd10_terms.itertuples():
code,terms = index[1],index[2]
data[code] = data['text_tokenized'].apply(get_sim, args=(terms,))