g_log.error()<<"The detector for spectrum number "<<mon0Spec<<" was either not found or is a group, grouped monitors are not supported by this algorithm\n";
g_log.error()<<"Error retrieving data for the first monitor"<<std::endl;
g_log.error()<<"The detector for spectrum number "<<mon1Spec<<" was either not found or is a group, grouped monitors are not supported by this algorithm\n";
g_log.error()<<"Error retrieving data for the second monitor\n";
// getting spectra numbers from detector IDs is hard because the map works the other way, getting index numbers from spectra numbers has the same problem and we are about to do both
// function adds zero if it can't find a detector into the new, probably large, multimap of detectorIDs to spectra numbers