Say we have this data: I want to count, for each year, how many rows (“index”) fall within each year, but excluding the Y0. So say we start at the first available year, 1990: How many rows do we count? 0. 1991: Three (row 1, 2, 3) 1992: Four (row 1, 2, 3, 4) … 2009: Four (row 1, 2,
Tag: pandas-groupby
GroupBy Column1, then get all elements with the first/last element on Column2 (Python)
I want to group by user_id, then get the first element of survey_id, and get all elements related to this selection In the same way I want to group by user_id, then get the last element of survey_id, and get all elements related to this selection Is there a quick groupby command to get this? I can do this by
Filter non-duplicated records in Python-pandas, based on group-by column and row-level comparison
This is a complicated issue and I am not able to figure this out, and I really appreciate your help in this. The below dataframe is generated from a pandas function DataFrame.duplicated(), based on ‘Loc'(groupby) and ‘Category’ repeated records are marked as True/False accordingly. My Expect…
Pandas: groupby().apply() custom function when groups variables aren’t the same length?
I have a large dataset of over 2M rows with the following structure: If I wanted to calculate the net debt for each person at each month I would do this: However the result is full of NA values, which I believe is a result of the dataframe not having the same amount of cash and debt variables for each
filter for rows with n largest values for each group
Context I want, for each team, the rows of the data frame that contains the top three scoring players. In my head, it is a combination of Dataframe.nlargest() and Dataframe.groupby() but I don’t think this is supported. My ideal solution is: performed directly on df without having to create other datafr…
Creating a new columns with maximum count of value in multiple columns
I have a dataframe that contains multiple columns as follow: I want to create a new column based on the player, competition and value of highest occurrence in Home column and Away column. Let’s say the name of a new column that I want to create is Team. I would like have a new column as follow: So it su…
How to change index and transposing in pandas
I’m new in pandas and trying to do some converting on the dateframe but I reach closed path. my data-frame is: I need this dataframe to be like the following: as it shown I take the entity_name column as index without duplicates and the columns names from request_status column and the value from dcount …
Custom Column Selection in Pandas DataFrame.Groupby.Agg’s dictionary
I have a problem in selecting what columns to be inserted in Pandas.DataFrame.Groupby.agg. Here’s the code to get and prepare the data. Which results in What I’ve done so far is that results in: The question is: How do I include other non numeric columns? How do I include other undetermined column…
Panda is printing true and false values
I have written some code to extract data in pandas, however i am getting true and false values and not the ouput extract data using groupby pandas Input file Output file should look like Output file looks like Goes on like this up to last line of data in input file Answer import pandas as pd df = pd.read_csv(…
GroupBy columns on column header prefix
I have a dataframe with column names that start with a set list of prefixes. I want to get the sum of the values in the dataframe grouped by columns that start with the same prefix. The only way I could figure out how to do it was to loop through the prefix list, get the columns from the dataframe