cf.h

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 *
 * @details
 * This file defines the @ref estimators::cf::CF class, which implements
 * a complementary filter for sensor fusion.
 *
 * A complementary filter combines measurements from different sensors
 * by exploiting their complementary frequency characteristics. For
 * example, a low-frequency measurement from one sensor can be combined
 * with a high-frequency measurement from another sensor to obtain a
 * more stable estimate.
 *
 * The filter parameters are defined by the cutoff frequency, time step,
 * time constant, and filter coefficient.
 *
 * @version 1.0
 * @date 2026-08-11
 *
 * @copyright
 * Copyright (c) 2026 Abhinay Kumar
 */
 
#ifndef ESTIMATORS_COMPLIMENTARY_FILTER
#define ESTIMATORS_COMPLIMENTARY_FILTER
 
namespace estimators
{

 
    namespace cf
    {

         */


         * @details
         * The CF class implements a first-order complementary filter that
         * combines two input measurements into a single filtered output.
         *
         * The filter can be configured using either the cutoff frequency
         * and sampling time or directly using the filter parameters.
         *
         * The class is templated so that the filter can operate on different
         * numeric types such as @c float or @c double.
         *
         * @tparam T Numeric data type used for the filter calculations.
         *
         * @par Typical usage
         * @code{.cpp}
         * estimators::cf::CF<double> filter;
         *
         * filter.init(2.5, 0.006);
         *
         * double output = filter.update(x1, x2);
         * @endcode
         */
        template <typename T>
        class CF
        {
        public:

             * @details
             * The filter parameters are initialized to zero. Use
             * @ref init() or the individual setter functions to configure
             * the filter before using @ref update().
             */
            CF();

            ~CF();

            /**
             * @brief Initializes the complementary filter.
             *
             * @param[in] fc_ Cutoff frequency of the filter.
             * @param[in] dt_ Sampling time or control-loop period.
             *
             * @details
             * This function initializes the filter parameters using the
             * specified cutoff frequency and sampling time.
             */
            void init(T fc_, T dt_);

            void set_param(T fc_, T dt_);

            T update(T x1_i, T x2_i);

            void reset();

            void set_fc(T fc_);

            void set_tau(T tau_);

            void set_dt(T dt_);

            void set_alpha(T alpha_);

            T get_fc();

            T get_tau();

            T get_dt();

            T get_alpha();
 
        private:
            T fc = 0.0;

            T tau = 0.0;

            T dt = 0.0;

            T alpha = 0.0;
        };
 
#include "CF.tpp"
 
    } // namespace cf
 
} // namespace estimators
 
#endif // ESTIMATORS_COMPLIMENTARY_FILTER