Handle object dtypes in EventTable.event_rate
This PR fixes a corner-case issue in EventTable.event_rate when numpy.histogram can't handle numpy.object_ dtypes. The fix is to cast these to float64 on-the-fly.
This PR fixes a corner-case issue in EventTable.event_rate when numpy.histogram can't handle numpy.object_ dtypes. The fix is to cast these to float64 on-the-fly.