Get week start date (Monday) from a date column in Python (pandas)?

Another alternative: df[‘week_start’] = df[‘myday’].dt.to_period(‘W’).apply(lambda r: r.start_time) This will set ‘week_start’ to be the first Monday before the time in ‘myday’. You can choose different week starts via anchored offsets e.g. ’W-THU’ to start the week on Thursday instead. (Thanks @Henry Ecker for that suggestion)

pandas columns correlation with statistical significance

To calculate all the p-values at once, you can use calculate_pvalues function (code below): df = pd.DataFrame({‘A’:[1,2,3], ‘B’:[2,5,3], ‘C’:[5,2,1], ‘D’:[‘text’,2,3] }) calculate_pvalues(df) The output is similar to the corr() (but with p-values): A B C A 0 0.7877 0.1789 B 0.7877 0 0.6088 C 0.1789 0.6088 0 Details: Column D is automatically ignored as it … Read more

How to provide a reproducible copy of your DataFrame with to_clipboard()

First: Do not post images of data, text only please Second: Do not paste data in the comments section or as an answer, edit your question instead How to quickly provide sample data from a pandas DataFrame There is more than one way to answer this question. However, this answer isn’t meant as an exhaustive … Read more

Why does pandas apply calculate twice

This behavior is intended, as an optimization. See the docs: In the current implementation apply calls func twice on the first column/row to decide whether it can take a fast or slow code path. This can lead to unexpected behavior if func has side-effects, as they will take effect twice for the first column/row.