How to use pd.melt to unpivot a dataframe where columns share a prefix? Question: I’m trying to unpivot my data using pd.melt but no success so far. Each row is a business, and the data contains information about the business and multiple reviews. I want my data to have every review as a row. My …
How to melt a dataframe so repeated items become the values that correspond to the index Question: I have this dataframe: df = pd.DataFrame({‘Status’:[‘CO’,’AD’,’AD’,’AD’,’OT’,’CO’,’OT’,’AD’], ‘Mutation’:[‘H157Y’,’R47H’,’R47H’,’R67H’,’R62H’,’D87N’,’D39E’,’D39E’]}) print(df) Status Mutation 0 CO H157Y 1 AD R47H 2 AD R47H 3 AD R67H 4 OT R62H 5 CO D87N 6 OT D39E 7 AD D39E I want the …
How to perform split/merge/melt with Python and polars? Question: I have a data transformation problem where the original data consists of "blocks" of three rows of data, where the first row denotes a ‘parent’ and the two others are related children. A minimum working example looks like this: import polars as pl df_original = pl.DataFrame( …
Chain df.str.split() in pandas dataframe Question: Edit: 2022NOV21 How do we chain df.col.str.split() since this returns the split columns if expand = True I am trying to split a column after performing .melt(). If I use assign I end up using the original column and the melted column actually does not even exist. df = …
How do I convert time series data from wide to long format using python (pandas package)? Question: I have some data taken at different time points in wide format, and need to convert it to long format to aid with analysis and to merge it with another dataset. The format of the data is (where …
How to aggregate DataFrame based on binnary and numeric columns in Python Pandas? Question: I have DataFrame in Python Pandas like below: ID | VAR1 | VAR2 | C1 | C2 —–|——|——|——|——- 111 | 1 | 0 | 12 | 0 222 | 1 | 1 | 11 | 18 333 | 0 | 1 …
How do I melt a pandas dataframe? Question: On the pandas tag, I often see users asking questions about melting dataframes in pandas. I am going to attempt a canonical Q&A (self-answer) with this topic. I am is going to clarify: What is melt? How do I use melt? When do I use melt? I …
PySpark Dataframe melt columns into rows Question: As the subject describes, I have a PySpark Dataframe that I need to melt three columns into rows. Each column essentially represents a single fact in a category. The ultimate goal is to aggregate the data into a single total per category. There are tens of millions of …
Pandas Melt several groups of columns into multiple target columns by name Question: I would like to melt several groups of columns of a dataframe into multiple target columns. Similar to questions Python Pandas Melt Groups of Initial Columns Into Multiple Target Columns and pandas dataframe reshaping/stacking of multiple value variables into seperate columns. However …
Melt the Upper Triangular Matrix of a Pandas Dataframe Question: Given a square pandas DataFrame of the following form: a b c a 1 .5 .3 b .5 1 .4 c .3 .4 1 How can the upper triangle be melted to get a matrix of the following form Row Column Value a a 1 …
