I just discovered that there is an easier way to do this (e.g. from tutorial06): import numpy.ma as ma mask = ma.masked_where(countries[‘ISO’] != iso, countries[‘ISO’]) country = ma.array(countries[‘country’],mask=mask.mask).compressed()[0] by using the built-in numpy.where method: import numpy as np index = np.where(countries[‘ISO’] == iso) country = countries[‘country’][index][0] Yeah, that’s fun ! The numpy.where method takes two…