feat(const): added constants class

constants class can parse and get physical constants from datafile including value, unit, uncertainity, and reference

src/const/public/const.h

@@ -7,52 +7,92 @@
 #include <vector>
 #include <map>
 
+/**
+ * @brief Structure to hold a constant's details.
+ */
 struct constant {
-  std::string name;
-  double value;
-  double uncertainty;
-  std::string unit;
-  std::string reference;
-}
+  std::string name;         ///< Name of the constant
+  double value;             ///< Value of the constant
+  double uncertainty;       ///< Uncertainty in the constant's value
+  std::string unit;         ///< Unit of the constant
+  std::string reference;    ///< Reference for the constant's value
+};
 
+/**
+ * @brief Class to manage a collection of constants.
+ */
 class constants {
 private:
-  bool loaded_ = false;
-  std::map<std::string, constant> constants_;
+  bool loaded_ = false; ///< Flag to indicate if constants are loaded
+  const int col_widths_[6] = {25, 52, 20, 20, 17, 45}; // From the python script used to generate the constants file
+  std::map<std::string, constant> constants_; ///< Map to store constants by name
 
+  /**
+   * @brief Load constants from a file.
+   * @param filename The name of the file to load constants from.
+   * @return True if loading was successful, false otherwise.
+   */
   bool load(const std::string& filename);
 
+  /**
+   * @brief Trim leading and trailing whitespace from a string.
+   * @param str The string to trim.
+   * @return The trimmed string.
+   */
+  std::string trim(const std::string& str);
+
 public:
+  /**
+   * @brief Default constructor.
+   */
   constants();
 
+  /**
+   * @brief Constructor that initializes constants from a file.
+   * @param filename The name of the file to load constants from.
+   */
   constants(const std::string& filename);
 
+  /**
+   * @brief Check if constants are loaded.
+   * @return True if constants are loaded, false otherwise.
+   */
   bool is_loaded() { return loaded_; }
 
+  /**
+   * @brief Initialize constants from a file.
+   * @param filename The name of the file to load constants from.
+   * @return True if initialization was successful, false otherwise.
+   */
   bool initialize(const std::string& filename);
 
+  /**
+   * @brief Get a constant by key.
+   * @param key The name of the constant to retrieve.
+   * @return The constant associated with the given key.
+   */
   constant get(const std::string& key);
 
-  constant operator[](const std::string& key) const {
-    auto it = constants_.find(key);
-    if (it != constants_.end()) {
-      return it->second;
-    } else {
-      throw std::out_of_range("Constant '" + key + "' not found.");
-    }
-  };
-  
-  bool has(const std::string& key) const {
-    return constants_.find(key) != constants_.end();
-  };
+  /**
+   * @brief Overloaded subscript operator to access constants by key.
+   * @param key The name of the constant to retrieve.
+   * @return The constant associated with the given key.
+   * @throws std::out_of_range if the key is not found.
+   */
+  constant operator[](const std::string& key) const;
 
-  std::Vector<std::string> keys() const {
-    std::Vector<std::string> keys;
-    for (auto it = constants_.begin(); it != constants_.end(); ++it) {
-      keys.push_back(it->first);
-    }
-    return keys;
-  };
+  /**
+   * @brief Check if a constant exists by key.
+   * @param key The name of the constant to check.
+   * @return True if the constant exists, false otherwise.
+   */
+  bool has(const std::string& key) const;
+
+  /**
+   * @brief Get a list of all constant keys.
+   * @return A vector of all constant keys.
+   */
+  std::set<std::string> keys() const;
 
 };