WIP: Add ReflectionTable class to allow efficient data access and fil…

…teringwq

include/dx2/reflection.hpp

@@ -0,0 +1,90 @@
+#ifndef DX2_REFLECTION_HPP
+#define DX2_REFLECTION_HPP
+
+#include "dx2/h5/h5read_processed.hpp"
+#include "dx2/tensor.hpp"
+#include <functional>
+#include <vector>
+
+class ReflectionTable {
+public:
+  /**
+   * @brief Enum representing the columns in the reflection table.
+   */
+  enum class Column { X = 0, Y = 1, Z = 2 };
+
+  /**
+   * @brief Default constructor
+   */
+  ReflectionTable() = default;
+
+  /**
+   * @brief Constructs a ReflectionTable from an HDF5 file.
+   *
+   * @param h5_filepath Path to the HDF5 file.
+   */
+  ReflectionTable(const std::string &h5_filepath)
+      : h5_filepath_(h5_filepath),
+        table_name_("/dials/processing/group_0/xyzobs.px.value") {}
+
+  /**
+   * @brief Selects reflections based on a predicate applied to a specified
+   * column.
+   *
+   * @param column The column to apply the predicate on (Column::X, Column::Y,
+   * Column::Z).
+   * @param predicate A function that returns `true` for rows to be kept.
+   */
+  void select(Column column, const std::function<bool(double)> &predicate) {
+    size_t column_index = static_cast<size_t>(column);
+
+    if (data_.size() == 0) {
+      load_data();
+    }
+    data_.remove_if(column_index, predicate);
+  }
+
+  /**
+   * @brief Retrieves a reference to a column's data.
+   *
+   * @param column The column to retrieve (Column::X, Column::Y, Column::Z).
+   * @return A vector containing the column's data.
+   */
+  std::vector<double> column(Column column) const {
+    size_t col_index = static_cast<size_t>(column);
+    std::vector<double> col_values(data_.shape()[0]);
+
+    for (size_t row = 0; row < data_.shape()[0]; ++row) {
+      col_values[row] = data_(row, col_index);
+    }
+    return col_values;
+  }
+
+private:
+  Tensor<double> data_;     // Internal tensor storing reflection data.
+  std::string table_name_;  // Name of the HDF5 table.
+  std::string h5_filepath_; // Path to the HDF5 file.
+
+  /**
+   * @brief Loads data from an HDF5 file into the tensor.
+   */
+  void load_data() {
+    // Read the data from the HDF5 file
+    H5Data<double> h5_data;
+    read_array_from_h5_file(h5_filepath_, table_name_, h5_data);
+
+    if (h5_data.shape.size() != 2) {
+      throw std::runtime_error("Error: Expected 2D data for reflection table.");
+    }
+    if (h5_data.shape[1] != 3) {
+      throw std::runtime_error(
+          "Error: Unexpected number of columns in reflection table.");
+    }
+
+    // Create the tensor and store the entire dataset
+    data_ = Tensor<double>(h5_data.shape, std::move(h5_data.data),
+                           Layout::RowMajor);
+  }
+};
+
+#endif // DX2_REFLECTION_HPP