LISTING 2.

Data can be filtered by a temporal or a spatiotemporal range using atl_filter_covariates. Filter conditions are passed to the filters argument as a character vector. Only rows in the data satisfying all the conditions are retained. Here, the first example shows how nighttime data can be retained using a predicate that determines whether the value of ‘hour’ is between 6 and 18, and also within a range of X coordinates. The second example retains ATLAS locations calculated using >3 base stations (NBS), with location error (SD) < 100, and data between an arbitrary day 5 and day 8