Latest Questions tagged Pandas

Browse all latest questions tagged Pandas

10
Votes
Published 24 Apr, 2022
Python - Pandas DataFrame: normalize one JSON column and merge with other columns

I have a pandas DataFrame containing one column with multiple JSON data items as list of dicts. I want to normalize the JSON column and duplicate the non-JSON columns: # creating dataframe df_actions...

71
Votes
Published 27 Aug, 2022
Python - Find rows of dataframe with the same column value in Pandas

Consider a dataframe with 2 columns for easiness. The first column is id and it is the key. The second column, named code is not a key but the case of two entries having the same value is very rare....

84
Votes
Published 31 Aug, 2022
Python - Write .csv file from pandas dataframe with consecutive spaces as delimiter

I want to write a text file which is separated by four spaces instead of one tab: df.to_csv(file,sep= '\s\s\s\s') instead of df.to_csv(file,sep= '\t') I tried regex : df.to_csv(file,sep= r'\s...

21
Votes
Published 31 Aug, 2022
Python - Create pandas dataframe from numpy array

To create a pandas dataframe from numpy I can use : columns = ['1','2'] data = np.array([[1,2] , [1,5] , [2,3]]) df_1 = pd.DataFrame(data,columns=columns) df_1 If I instead use : columns = ['1',...

24
Votes
Published 08 May, 2022
Python - Pandas Correlation Groupby

Assuming I have a dataframe similar to the below, how would I get the correlation between 2 specific columns and then group by the 'ID' column? I believe the Pandas 'corr' method finds the correlatio...

21
Votes
Published 08 May, 2022
Python - Plyr or dplyr in Python

This is more of a conceptual question, I do not have a specific problem. I am learning python for data analysis, but I am very familiar with R - one of the great things about R is plyr (and of course...

70
Votes
Published 20 Aug, 2022
Python - How to compare two data frame and get the unmatched rows using python?

I have two data frames, df1 and df2. Now, df1 contains 6 records and df2 contains 4 records. I want to get the unmatched records out of it. I tried it but getting an error ValueError: Can only compare...

42
Votes
Published 29 Aug, 2022
Python - pandas 0.24.1 Key Error: "None of [Index(['A' 'B'], dtype='object')] are in the [columns]"

Formerly I had anaconda with pandas 0.18. Using the code below, I made a calculation by the function "calc_func" and assign the result to the the columns of DataFrame, say "A" and "B". df[["A", "B"]]...

43
Votes
Published 27 Aug, 2022
Python - Python pandas dataframe group by based on a condition

My question is simple, I have a dataframe and I groupby the results based on a column and get the size like this: df.groupby('column').size() Now the problem is that I only want the ones where size...

59
Votes
Published 23 Aug, 2022
Python - pandas groupby column and check if group meets multiple conditions

I have a DataFrame that looks like the following: X Y Date are_equal 0 50.0 10.0 2018-08-19 False 1 NaN 10.0 2018-08-19 False 2 NaN 50.0 2018-08-1...

18
Votes
Published 27 Aug, 2022
Python - Adding Multiple Values into a Column - Pandas

I have two pandas dataframes that Im trying to merge together on their ID number. However in df1 the ID is being used multiple times and in df2 it is only being used once. Therefore I want the final d...

69
Votes
Published 29 Aug, 2022
Python - Fast way to split column into multiple rows in Pandas

I have the following data frame: import pandas as pd df = pd.DataFrame({ 'gene':["foo", "bar // lal", "qux", "woz"]...

16
Votes
Published 26 Aug, 2022
Python - pandas: drop duplicates in groupby 'date'

In the dataframe below, I would like to eliminate the duplicate cid values so the output from df.groupby('date').cid.size() matches the output from df.groupby('date').cid.nunique(). I have looked at...

91
Votes
Published 26 Aug, 2022
Python - Fill in empty header with previous column name - pandas

I have a dataframe where each second column name is skipped: eg Step_1. The idea is to fill unnamed columns with previous name to get: Step_2. To sum up "in" and "out" in each class, to get fi...

33
Votes
Published 25 Aug, 2022
Python - Convert a dictionary to DataFrame with specified column names

I have a dictionary which is dict['TimeStamp'] = [value1,value2,value3] the dict has many times stamps and each time stamp has 3 values for example I want to make panda dataframe of all values of dict...