Convert categorical variables to numeric with pandas Forward- or back-fill NA values in DataFrames Cross-join two pandas DataFrames Create a DataFrame of zeros or nulls Use date indexes with pandas DataFrames Use all options of pandas DataFrame info() Get differences between two pandas DataFrames Explode and regroup lists into rows in a pandas DataFrame Flatten JSON files with pandas Flatten multi-index columns in pandas DataFrames Aggregate a pandas DataFrame on multiple functions Display more DataFrame cells in Jupyter notebooks Read multiple CSV files into a pandas DataFrame Use a column value if not Null, or another column from a pandas DataFrame Pivot pandas Dataframes with non-numeric values Rename pandas DataFrame columns with method chaining Calculate moving averages and rolling windows with pandas Select rows with NA values in any pandas DataFrame column Split values into columns of a pandas DataFrame Get top rows or random rows within groups in a DataFrame Apply computation within groups in a pandas DataFrame Go up a hierarchical tree with pandas Make full use of pandas value_counts() Get first row(s) of each group Floor datetimes and dates Convert nested string field to dict in Python Get today and yesterday date in Python List files in a folder with Python Read and write to Google Sheets with Python Handle infinity values in Python Get common elements between lists in Python Open and read/write files in Python Rearrange layers with Matplotlib and Seaborn plots in Python Plot beautiful time series with Python seaborn Train Machine Learning algorithms with Python scikit-learn Plot great categorical distribution graphs with Python seaborn Get the perfect color palette with Seaborn Manage markers for lineplots with Python seaborn Split ML data into training and test sets in Python Manually create a legend on a Matplotlib plot Query on time window in SQL Convert rows to columns with PIVOT in BigQuery Calculate period-to-period change in SQL Count words and characters in a string with PostgreSQL Calculate cumulative sum in SQL Substract days to a date in SQL Compute time intervals in PostgreSQL Import foreign PostgreSQL database Filter with HAVING clause in SQL Join on multiple SQL tables with fallback on first non-Null value Join tables in SQL with multiple ON conditions Avoid division by zero errors in SQL Rank results in SQL with RANK, DENSE_RANK and ROW_NUMBER Convert between epoch and datetime in Redshift Query new vs returning users in SQL Get rolling average in SQL Round timestamp to the nearest minute, hour… in PostgreSQL Compute sessions and streaks in SQL Count the next occurences within a time window Get percentiles in Redshift Compute percent of column Get first or last value in a group Combine ‘cd’ & ‘ls’ into a single command Compress and decompress files on Linux Batch convert files encoding in Terminal Delete all .DS_Store files on MacOS Find files matching pattern in Terminal Resize picture zone in MacOS Preview