File content as of revision 23:5238b046119b:

#ifndef _PID_SOURCE_
#define _PID_SOURCE_

#include <iostream>
#include <cmath>
#include "pid.h"

using namespace std;

PID::PID( float dt, float max, float min, float kp, float ki, float kd )
{
   dt_ = dt;
   max_ = max;
   min_ = min;
   kp_ = kp;
   ki_ = ki;
   kd_ = kd;
   pre_error_ = 0;
   integral_ = 0;
   
}

float PID::calculate(float setpoint, float pv)
{
    // Calculate time changed since last PID calculation
//    dt_ = current_time - dt_;
       
    // Calculate error
    float error = setpoint - pv;

    // Proportional term
    float Pout = kp_ * error;

    // Integral term
    integral_ += error * dt_;
    float Iout = ki_ * integral_;

    // Derivative term
    float derivative = (error - pre_error_) / dt_;
    float Dout = kd_ * derivative;

    // Calculate total output
    float output = Pout + Iout + Dout;

    // Restrict to max/min

    if( output > max_ ){
        output = max_;
    }
    else if( output < min_ ){
        output = min_;
    }


    // Save error to previous error
    pre_error_ = error;

    return output;
}

void PID::testError(float setpoint, float pv){
        float error = setpoint - pv;
        printf("Error: %f\n", error);
        printf("Change in Time: %f\n", dt_);
}

PID::~PID() {}


/**
 * Implementation
 */
/*
PIDImpl::PIDImpl( float dt, float max, float min, float Kp, float Kd, float Ki ) :
    _dt(dt),
    _max(max),
    _min(min),
    _Kp(Kp),
    _Kd(Kd),
    _Ki(Ki),
    _pre_error(0),
    _integral(0)
{
}

float PIDImpl::calculate( float setpoint, float pv )
{
    
    // Calculate error
    float error = setpoint - pv;

    // Proportional term
    float Pout = _Kp * error;

    // Integral term
    _integral += error * _dt;
    float Iout = _Ki * _integral;

    // Derivative term
    float derivative = (error - _pre_error) / _dt;
    float Dout = _Kd * derivative;

    // Calculate total output
    float output = Pout + Iout + Dout;

    // Restrict to max/min
    if( output > _max )
        output = _max;
    else if( output < _min )
        output = _min;

    // Save error to previous error
    _pre_error = error;

    return output;
}

PIDImpl::~PIDImpl()
{
}
*/
#endif