pandas

Best of pandas

• Chain an arbitrary number of selection conditions - kudos to https://stackoverflow.com/a/64945576

  import pandas as pd
  df = pd.DataFrame({
      'var1': [1, 2, 3, 4, 1, 2, 3, 4],
      'var2': ['a', 'b', 'a', 'b', 'a', 'b', 'a', 'b'],
      'var3': [8, 7, 6, 5, 4, 3, 2, 1]
  })
  
  # specify an arbitrary number of conditions
  variables = ['var1', 'var2']
  values    = [1, 'a']
  
  # identify the (row) indices for which the conditions are fulfilled
  locator = pd.concat(
      [(df[col] == val) for col, val in zip(variables, values)], axis='columns'
  ).all(axis='columns')
  
  print(df.loc[locator])