void
DataSetIO::SaveDataSet(const DataSet& dataSet_, const std::string& filename_){
// Get the relevant params
hsize_t nEntries = dataSet_.GetNEntries();
hsize_t nObs = dataSet_.GetNObservables();
hsize_t nData = nObs * nEntries;
// create colon separated string from list of observables
std::vector<std::string> observableNames = dataSet_.GetObservableNames();
if (observableNames.size() != nObs)
throw HdfIOError("SaveDataSet::Require one name and one name only for each observable");
// Set up files
H5::H5File file(filename_, H5F_ACC_TRUNC);
// Flatten data into 1D array
// HDF5 likes c arrays. Here use a vector and pass pointer to first element
// memory guaranteed to be contiguous
std::vector<double> flattenedData;
std::vector<double> eventData;
flattenedData.reserve(nData);
for(size_t i = 0; i < nEntries; i++){
eventData = dataSet_.GetEntry(i).GetData();
flattenedData.insert(flattenedData.end(), eventData.begin(), eventData.end());
}
// Set up the data set
// 1D, ndata long, called "observations". Saved as native doubles on this computer
H5::DataSpace dataSpace(1, &nData);
H5::DataSet theData(file.createDataSet("observations", H5::PredType::NATIVE_DOUBLE, dataSpace));
// Set up the attributes - the number of obs per event and the names of the observables
// 64 chars max in str to save space
H5::StrType strType(H5::PredType::C_S1, 64);
H5::DataSpace attSpace(H5S_SCALAR);
H5::Attribute obsListAtt = theData.createAttribute("observed_quantities", strType, attSpace);
obsListAtt.write(strType, FlattenStringVector(observableNames, fDelimiter));
H5::Attribute countAtt = theData.createAttribute("n_observables",
H5::PredType::NATIVE_INT,
attSpace);
countAtt.write(H5::PredType::NATIVE_INT, &nObs);
// Write the data
theData.write(&flattenedData.at(0), H5::PredType::NATIVE_DOUBLE);
}
