/** Creates a mapping based on a fixed number of groups for a given instrument
*component
*
* @param compName Name of component in instrument
* @param numGroups Number of groups to group detectors into
* @param inst Pointer to instrument
* @param prog Progress reporter
* @returns :: Map of detector IDs to group number
*/
std::map<detid_t, int> makeGroupingByNumGroups(const std::string compName,
int numGroups,
Instrument_const_sptr inst,
Progress &prog) {
std::map<detid_t, int> detIDtoGroup;
// Get detectors for given instument component
std::vector<IDetector_const_sptr> detectors;
inst->getDetectorsInBank(detectors, compName);
size_t numDetectors = detectors.size();
// Sanity check for following calculation
if (numGroups > static_cast<int>(numDetectors))
throw std::runtime_error("Number of groups must be less than or "
"equal to number of detectors");
// Calculate number of detectors per group
int detectorsPerGroup = static_cast<int>(numDetectors) / numGroups;
// Map detectors to group
for (unsigned int detIndex = 0; detIndex < numDetectors; detIndex++) {
int detectorID = detectors[detIndex]->getID();
int groupNum = (detIndex / detectorsPerGroup) + 1;
// Ignore any detectors the do not fit nicely into the group divisions
if (groupNum <= numGroups)
detIDtoGroup[detectorID] = groupNum;
prog.report();
}
return detIDtoGroup;
}
