Create hdf5_save.cpp

Author: TimGoTheCreator

src/io/hdf5_save.cpp

@@ -0,0 +1,60 @@
+#include "hdf5_save.h"
+#include <hdf5.h>
+#include <vector>
+#include <string>
+
+void SaveHDF5(const std::vector<Particle>& p, const std::string& filename)
+{
+    hid_t file = H5Fcreate(filename.c_str(), H5F_ACC_TRUNC, H5P_DEFAULT, H5P_DEFAULT);
+
+    // Group: PartType1 (DM)
+    hid_t group = H5Gcreate(file, "PartType1", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+
+    size_t N = p.size();
+
+    // Prepare arrays
+    std::vector<float> coords(N * 3);
+    std::vector<float> vels(N * 3);
+    std::vector<float> masses(N);
+    std::vector<int> ids(N);
+
+    for (size_t i = 0; i < N; i++) {
+        coords[3*i+0] = p[i].x;
+        coords[3*i+1] = p[i].y;
+        coords[3*i+2] = p[i].z;
+
+        vels[3*i+0] = p[i].vx;
+        vels[3*i+1] = p[i].vy;
+        vels[3*i+2] = p[i].vz;
+
+        masses[i] = p[i].m;
+        ids[i] = i + 1; // Gadget requires IDs
+    }
+
+    // Dataspace for Nx3
+    hsize_t dims3[2] = { N, 3 };
+    hid_t space3 = H5Screate_simple(2, dims3, NULL);
+
+    // Dataspace for N
+    hsize_t dims1[1] = { N };
+    hid_t space1 = H5Screate_simple(1, dims1, NULL);
+
+    // Write datasets
+    H5Dcreate(group, "Coordinates", H5T_NATIVE_FLOAT, space3, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    H5Dwrite(H5Dopen(group, "Coordinates", H5P_DEFAULT), H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL, H5P_DEFAULT, coords.data());
+
+    H5Dcreate(group, "Velocities", H5T_NATIVE_FLOAT, space3, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    H5Dwrite(H5Dopen(group, "Velocities", H5P_DEFAULT), H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL, H5P_DEFAULT, vels.data());
+
+    H5Dcreate(group, "Masses", H5T_NATIVE_FLOAT, space1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    H5Dwrite(H5Dopen(group, "Masses", H5P_DEFAULT), H5T_NATIVE_FLOAT, H5S_ALL, H5S_ALL, H5P_DEFAULT, masses.data());
+
+    H5Dcreate(group, "ParticleIDs", H5T_NATIVE_INT, space1, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
+    H5Dwrite(H5Dopen(group, "ParticleIDs", H5P_DEFAULT), H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, ids.data());
+
+    // Cleanup
+    H5Sclose(space3);
+    H5Sclose(space1);
+    H5Gclose(group);
+    H5Fclose(file);
+}