Arduino 3 & 5 point running median

Functions for fast 3-point and 5-point median filter, for either integer or float/double var types.
Example shows random data stream with real-time running median filtering.

 Snippet   (Full current code on github at https://github.com/davidsmith99/median )

// the function (calls another function 'swap()' not shown here
double median3( double a0, double a1, double a2 ) {
  swap(&a1, &a2); // swaps values  if arg1 > arg2
  swap(&a0, &a2);
  swap(&a0, &a1);

  return a1; // median value
}

//using in a loop
void loop() {
  // generate random data with outliers to observe median filtering

  // use 3 most recent values
  // drop val_prev2 value and update the latest value
  fval_prev2 = fval_prev1;
  fval_prev1 = fval_new;
  fval_new = 0.99 * (10 + random(-2, 8) + (random(0, 4) == 0) * 4 * (random(0, 5))); // small variation plus occasional spikes

 double fmedian = median3(fval_prev2, fval_prev1, fval_new);
 Serial.print(fval_new); Serial.print("\t");
 Serial.print(fmedian);  Serial.print("\n");
 delay(200);
}

Other related links:

http://playground.arduino.cc/Main/RunningMedian

reference on function overloading c++
http://www.programmingsimplified.com/cpp/source-code/cpp-function-overloading-example-program