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); }