StDetectorDbInterpolator.h

#ifndef StDetectorDbInterpolator_h
#define StDetectorDbInterpolator_h

template<class T>
class StDetectorDbInterpolator{
public:
    StDetectorDbInterpolator(unsigned int numEntries,unsigned int* times,T* array);
    T interpolate(unsigned int time);
    T getLowerValue(unsigned int time);
private:
    unsigned int mNumEntries;
    unsigned int* mTimes;
    T* mArray;
};

template<class T>
StDetectorDbInterpolator<T>::StDetectorDbInterpolator(unsigned int numEntries,unsigned int* times,T* array){
    mNumEntries = numEntries;
    mTimes = times;
    mArray = array;
};

template<class T>
T StDetectorDbInterpolator<T>::interpolate(unsigned int time){

    if( mNumEntries == 0)
        return 0;
    
    if(time <= mTimes[0])
        return mArray[0];
    if(time >= mTimes[mNumEntries-1])
        return mArray[mNumEntries-1];
    unsigned int i = 0;
    while(mTimes[i] < time && i < mNumEntries)
        i++;
    double relTime = (time - mTimes[i-1]);
    double denominator = (mTimes[i]-mTimes[i-1]);

    if(denominator == 0)
        return mArray[i];
    else
        return (relTime/denominator)*(mArray[i]-mArray[i-1])+mArray[i-1];
    
};

template<class T>
T StDetectorDbInterpolator<T>::getLowerValue(unsigned int time){

    if( mNumEntries == 0)
        return 0;
    
    if(time <= mTimes[0])
        return mArray[0];
    if(time >= mTimes[mNumEntries-1])
        return mArray[mNumEntries-1];

    unsigned int i = 0;
    
    
    while(mTimes[i] < time && i < mNumEntries){
      i++;
    }
    
    if(i > 0){
      i--;
    }

    return mArray[i];
        
};

#endif