Merge pull request #48 from V0v1kkk/master

Added functions for calculating standard deviation and standard error, function for check fullness of buffer.

libraries/RunningAverage/RunningAverage.cpp

@@ -25,12 +25,13 @@
 // 0.2.10 - 2015-09-01 added getFastAverage() and refactored getAverage()
 //                     http://forum.arduino.cc/index.php?topic=50473
 // 0.2.11 - 2015-09-04 added getMaxInBuffer() getMinInBuffer() request (Antoon)
-//
+// 0.2.12 - 2016-12-01 added GetStandardDeviation() GetStandardError() BufferIsFull()  (V0v1kkk)
 // Released to the public domain
 //
 
 #include "RunningAverage.h"
 #include <stdlib.h>
+#include <math.h>
 
 RunningAverage::RunningAverage(const uint8_t size)
 {
@@ -119,6 +120,13 @@ double RunningAverage::GetMaxInBuffer() const
     return max;
 }
 
+// return true if buffer is full
+bool RunningAverage::BufferIsFull() const
+{
+    if (_cnt == _size) return true;
+    return false;
+}
+
 // returns the value of an element if exist, NAN otherwise
 double RunningAverage::getElement(uint8_t idx) const
 {
@@ -126,6 +134,32 @@ double RunningAverage::getElement(uint8_t idx) const
     return _ar[idx];
 }
 
+// Return standard deviation of running average. If buffer is empty, return NAN.
+double RunningAverage::GetStandardDeviation() const
+{
+	if (_cnt == 0) return NAN;
+    double temp = 0;
+	double average = getFastAverage();
+    for (uint8_t i = 0; i < _cnt; i++)
+    {
+		temp += pow((_ar[i] - average),2);
+    }
+	temp = sqrt(temp/(_cnt - 1));
+    return temp;
+}
+
+// Return standard error of running average. If buffer is empty, return NAN.
+double RunningAverage::GetStandardError() const //++
+{
+	double temp = GetStandardDeviation();
+	if(temp==NAN) return NAN;
+	double n;
+	if(_cnt>=30) n= _cnt;
+	else n= _cnt - 1;
+	temp = temp/sqrt(n);
+	return temp;
+}
+
 // fill the average with a value
 // the param number determines how often value is added (weight)
 // number should preferably be between 1 and size

libraries/RunningAverage/RunningAverage.h

@@ -1,8 +1,8 @@
 //
 //    FILE: RunningAverage.h
 //  AUTHOR: Rob dot Tillaart at gmail dot com
-// VERSION: 0.2.11
-//    DATE: 2015-sep-04
+// VERSION: 0.2.12
+//    DATE: 2016-dec-01
 // PURPOSE: RunningAverage library for Arduino
 //     URL: http://arduino.cc/playground/Main/RunningAverage
 // HISTORY: See RunningAverage.cpp
@@ -17,7 +17,7 @@
 #ifndef RunningAverage_h
 #define RunningAverage_h
 
-#define RUNNINGAVERAGE_LIB_VERSION "0.2.11"
+#define RUNNINGAVERAGE_LIB_VERSION "0.2.12"
 
 #include "Arduino.h"
 
@@ -35,18 +35,27 @@ public:
     double getAverage() const;      // does iterate over all elements.
     double getFastAverage() const;  // reuses previous values.
 
-    // returns min/max added to the data-set since last clear
+	// return statistical characteristics of the running average
+    double GetStandardDeviation() const; 
+	double GetStandardError() const;
+	
+	// returns min/max added to the data-set since last clear
     double getMin() const { return _min; };
     double getMax() const { return _max; };
 
-    // returns min/max from the values in the internal buffer
+	// returns min/max from the values in the internal buffer
     double GetMinInBuffer() const;
     double GetMaxInBuffer() const;
+	
+	// return true if buffer is full
+	bool BufferIsFull() const;
 
     double getElement(uint8_t idx) const;
 
     uint8_t getSize() const { return _size; }
     uint8_t getCount() const { return _cnt; }
+	
+	
 
 protected:
     uint8_t _size;

libraries/RunningAverage/keywords.txt

@@ -21,7 +21,10 @@ fillValue	KEYWORD2
 getElement	KEYWORD2
 getSize	KEYWORD2
 getCount	KEYWORD2
+BufferIsFull()	KEYWORD2
 getFastAverage	KEYWORD2
+GetStandardDeviation	KEYWORD2
+GetStandardError	KEYWORD2
 GetMinInBuffer	KEYWORD2
 GetMaxInBuffer	KEYWORD2