Simple Data Statistics (Temperature)

1#include "AvgStd.h"
2#include <LiquidCrystal.h>
3
4LiquidCrystal   lcd(12,11,5,4,3,2);
5const int sensorPin = A0;
6AvgStd mySamples;
7
8void   setup(){
9  mySamples = AvgStd();
10  mySamples.setRejectionSigma(7.0);
11  Serial.begin(9600);
12   while (!Serial) {
13    ; // wait for serial port to connect. Needed for native   USB port only
14  }
15
16  // send an intro:
17  Serial.println("\
18\
19AvgStd:");
20   Serial.println();
21  lcd.begin(16, 2);
22  // Print a message to the LCD.
23   lcd.print("hello, world!");
24  }
25
26void loop(){
27  
28  // read temperature
29   float T = readTemperature();
30  mySamples.checkAndAddReading(T);
31
32  //   print string
33  //
34  lcdPrint(T);
35
36   //if reset button pressed
37   //   mySamples.reset();
38   delay(1000);
39  }
40
41float readTemperature(){
42   //read device
43  int v = analogRead(sensorPin);
44  // convert to V (ADC 1024   values, 5V max)
45  // float vr = ((float)v / 1024.0) * 5.0;  
46  // T = ( v   [V] - 0.5 V) * 100 [C]
47  return 100 * ((((float)v / 1024.0) * 5.0) - 0.5);
48   }
49
50void serialPrint(float T){
51  Serial.print("T = " + String(T, 2));
52   Serial.println(" N = " + String(mySamples.getN()));
53  Serial.print("avg:   " + String(mySamples.getMean(),2));
54  Serial.println(" +- " + String(mySamples.getStd(),2));
55   Serial.print("min: " + String(mySamples.getMin(),2));
56  Serial.println("   max: " + String(mySamples.getMax(),2));
57  
58  }
59
60void lcdPrint(float   T){
61  lcd.clear();
62  // print first row with avg/std
63  lcd.setCursor(0,0);
64   String a = "T=" + String(mySamples.getMean(),2);
65  lcd.print(a);
66  lcd.setCursor(8,0);
67   a = "+- " + String(mySamples.getStd(),2);
68  lcd.print(a);
69  lcd.setCursor(15,0);
70   lcd.print( mySamples.getN()%2 == 0? "* " : "  " );
71  // second row alternates   min/max with current reading
72  lcd.setCursor(0,1);
73  if ((mySamples.getN()/10)%2   == 0){
74    //display avg+std
75    lcd.setCursor(0,1);
76    
77    a = "   " + String(T,2) + " N=" + String(mySamples.getN());
78    lcd.print(a);
79     
80  } else {
81    // display min/max
82    a = "m " + String(mySamples.getMin(),2);
83     lcd.print(a);
84    lcd.setCursor(9,1);
85    a = "M " + String(mySamples.getMax(),2);
86     lcd.print(a);
87    }
88  
89}
90

1/**
2 * Library to calculate the average and standard deviation of a
3  
4 * reading iteratively: without storing the whole data set.
5 * 
6 * Stores:
7  
8 * double average
9 * double variance
10 * int numberOfReadings
11 * double
12  min
13 * double max
14 **/
15 
16 /* 
17Copyright (c) 2016 Edoardo Pasca
18
19Permission
20  is hereby granted, free of charge, to any person obtaining a copy of this software
21  and associated documentation files (the "Software"), to deal in the Software without
22  restriction, including without limitation the rights to use, copy, modify, merge,
23  publish, distribute, sublicense, and/or sell copies of the Software, and to permit
24  persons to whom the Software is furnished to do so, subject to the following conditions:
25
26The
27  above copyright notice and this permission notice shall be included in all copies
28  or substantial portions of the Software.
29
30THE SOFTWARE IS PROVIDED "AS IS",
31  WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
32  WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
33  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
34  OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
35  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
36  THE SOFTWARE.
37 */
38 
39#include "AvgStd.h"
40#include <math.h>
41
42
43AvgStd::AvgStd(){
44
45    AvgStd::reset();
46}
47
48void AvgStd::checkAndAddReading(float val){
49
50
51    if (N < 10) 
52        AvgStd::addReading(val);
53    else {
54        if
55  (r_sigma == -1) 
56            AvgStd::addReading(val);
57        else {
58            if
59  (abs(avg - val) <= (r_sigma * sqrt(var)) )
60                AvgStd::addReading(val);
61
62        }
63    }
64
65}
66
67void AvgStd::addReading(float val){
68        
69
70    if (N == 0) {
71        avg = val;
72        min = val;
73        max = val;
74
75    } else if (N == 1) {
76        //set min/max
77        max = val > max? val
78  : max;
79        min = val < min? val : min;        
80            
81        
82
83        float thisavg = (avg + val)/2;
84        // initial value is in avg
85
86        var = (avg - thisavg)*(avg-thisavg) + (val - thisavg) * (val-thisavg);
87
88        avg = thisavg;
89    } else {
90        // set min/max
91        max
92  = val > max? val : max;
93        min = val < min? val : min;        
94        
95
96        float M = (float)N;
97
98        var = var * ((M-1)/M) + ((val - avg)*(val
99  - avg)/(M+1)) ;
100        
101        avg = avg * (M/(M+1)) + val / (M+1);
102
103    }
104    N++;
105}
106
107
108
109void AvgStd::reset(){
110    N = 0;
111    avg
112  = 0;
113    var = 0;
114    min = 0;
115    max = 0;
116    r_sigma = -1;
117}
118
119float
120  AvgStd::getMean(){return avg;}
121float AvgStd::getStd() {
122    float ret = -1;
123
124    if (N>1)
125        ret = sqrt(var);
126    return ret;
127}
128float AvgStd::getVariance()
129  {return var;}
130unsigned int AvgStd::getN(){return N;}
131float AvgStd::getMin()
132  {return min;}
133float AvgStd::getMax() {return max;}
134
135void AvgStd::setRejectionSigma(float
136  sigmas){
137    r_sigma = sigmas;
138};
139    
140

1#include "AvgStd.h"
2#include <LiquidCrystal.h>
3
4LiquidCrystal  lcd(12,11,5,4,3,2);
5const int sensorPin = A0;
6AvgStd mySamples;
7
8void  setup(){
9  mySamples = AvgStd();
10  mySamples.setRejectionSigma(7.0);
11  Serial.begin(9600);
12  while (!Serial) {
13    ; // wait for serial port to connect. Needed for native  USB port only
14  }
15
16  // send an intro:
17  Serial.println("\
18\
19AvgStd:");
20  Serial.println();
21  lcd.begin(16, 2);
22  // Print a message to the LCD.
23  lcd.print("hello, world!");
24  }
25
26void loop(){
27  
28  // read temperature
29  float T = readTemperature();
30  mySamples.checkAndAddReading(T);
31
32  //  print string
33  //
34  lcdPrint(T);
35
36   //if reset button pressed
37   //  mySamples.reset();
38   delay(1000);
39  }
40
41float readTemperature(){
42  //read device
43  int v = analogRead(sensorPin);
44  // convert to V (ADC 1024  values, 5V max)
45  // float vr = ((float)v / 1024.0) * 5.0;  
46  // T = ( v  [V] - 0.5 V) * 100 [C]
47  return 100 * ((((float)v / 1024.0) * 5.0) - 0.5);
48  }
49
50void serialPrint(float T){
51  Serial.print("T = " + String(T, 2));
52  Serial.println(" N = " + String(mySamples.getN()));
53  Serial.print("avg:  " + String(mySamples.getMean(),2));
54  Serial.println(" +- " + String(mySamples.getStd(),2));
55  Serial.print("min: " + String(mySamples.getMin(),2));
56  Serial.println("  max: " + String(mySamples.getMax(),2));
57  
58  }
59
60void lcdPrint(float  T){
61  lcd.clear();
62  // print first row with avg/std
63  lcd.setCursor(0,0);
64  String a = "T=" + String(mySamples.getMean(),2);
65  lcd.print(a);
66  lcd.setCursor(8,0);
67  a = "+- " + String(mySamples.getStd(),2);
68  lcd.print(a);
69  lcd.setCursor(15,0);
70  lcd.print( mySamples.getN()%2 == 0? "* " : "  " );
71  // second row alternates  min/max with current reading
72  lcd.setCursor(0,1);
73  if ((mySamples.getN()/10)%2  == 0){
74    //display avg+std
75    lcd.setCursor(0,1);
76    
77    a = "  " + String(T,2) + " N=" + String(mySamples.getN());
78    lcd.print(a);
79    
80  } else {
81    // display min/max
82    a = "m " + String(mySamples.getMin(),2);
83    lcd.print(a);
84    lcd.setCursor(9,1);
85    a = "M " + String(mySamples.getMax(),2);
86    lcd.print(a);
87    }
88  
89}
90

1/**
2 * Library to calculate the average and standard deviation of a  
3 * reading iteratively: without storing the whole data set.
4 * 
5 * Stores:  
6 * double average
7 * double variance
8 * int numberOfReadings
9 * double  min
10 * double max
11 **/
12 
13 /* 
14Copyright (c) <year> <copyright holders>
15
16Permission  is hereby granted, free of charge, to any person obtaining a copy of this software  and associated documentation files (the "Software"), to deal in the Software without  restriction, including without limitation the rights to use, copy, modify, merge,  publish, distribute, sublicense, and/or sell copies of the Software, and to permit  persons to whom the Software is furnished to do so, subject to the following conditions:
17
18The  above copyright notice and this permission notice shall be included in all copies  or substantial portions of the Software.
19
20THE SOFTWARE IS PROVIDED "AS IS",  WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE  WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES  OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN  THE SOFTWARE.
21 */
22
23 #ifndef AVGSTD_H
24 #define AVGSTD_H
25
26 #include  "Arduino.h"
27
28class AvgStd {
29  public:
30    float getMean();
31    float  getStd();
32    float getMin();
33    float getMax();
34    float getVariance();
35    unsigned int getN();
36    void reset();
37    void addReading(float);
38    void checkAndAddReading(float);
39    void setRejectionSigma(float);
40    int  getTrend();
41    void setTrendInterval(int);
42    void setSamplingInterval(int);
43    AvgStd();
44  private:
45    float min, max, var, avg, r_sigma;
46    unsigned  int N;
47  
48  };
49
50 #endif
51

1/**
2 * Library to calculate the average and standard deviation of a  
3 * reading iteratively: without storing the whole data set.
4 * 
5 * Stores:  
6 * double average
7 * double variance
8 * int numberOfReadings
9 * double  min
10 * double max
11 **/
12 
13 /* 
14Copyright (c) 2016 Edoardo Pasca
15
16Permission  is hereby granted, free of charge, to any person obtaining a copy of this software  and associated documentation files (the "Software"), to deal in the Software without  restriction, including without limitation the rights to use, copy, modify, merge,  publish, distribute, sublicense, and/or sell copies of the Software, and to permit  persons to whom the Software is furnished to do so, subject to the following conditions:
17
18The  above copyright notice and this permission notice shall be included in all copies  or substantial portions of the Software.
19
20THE SOFTWARE IS PROVIDED "AS IS",  WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE  WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES  OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN  THE SOFTWARE.
21 */
22 
23#include "AvgStd.h"
24#include <math.h>
25
26
27AvgStd::AvgStd(){
28    AvgStd::reset();
29}
30
31void AvgStd::checkAndAddReading(float val){
32
33    if (N < 10) 
34        AvgStd::addReading(val);
35    else {
36        if  (r_sigma == -1) 
37            AvgStd::addReading(val);
38        else {
39            if  (abs(avg - val) <= (r_sigma * sqrt(var)) )
40                AvgStd::addReading(val);
41        }
42    }
43
44}
45
46void AvgStd::addReading(float val){
47        
48    if (N == 0) {
49        avg = val;
50        min = val;
51        max = val;
52    } else if (N == 1) {
53        //set min/max
54        max = val > max? val  : max;
55        min = val < min? val : min;        
56            
57        
58        float thisavg = (avg + val)/2;
59        // initial value is in avg
60        var = (avg - thisavg)*(avg-thisavg) + (val - thisavg) * (val-thisavg);
61        avg = thisavg;
62    } else {
63        // set min/max
64        max  = val > max? val : max;
65        min = val < min? val : min;        
66        
67        float M = (float)N;
68
69        var = var * ((M-1)/M) + ((val - avg)*(val  - avg)/(M+1)) ;
70        
71        avg = avg * (M/(M+1)) + val / (M+1);
72    }
73    N++;
74}
75
76
77
78void AvgStd::reset(){
79    N = 0;
80    avg  = 0;
81    var = 0;
82    min = 0;
83    max = 0;
84    r_sigma = -1;
85}
86
87float  AvgStd::getMean(){return avg;}
88float AvgStd::getStd() {
89    float ret = -1;
90    if (N>1)
91        ret = sqrt(var);
92    return ret;
93}
94float AvgStd::getVariance()  {return var;}
95unsigned int AvgStd::getN(){return N;}
96float AvgStd::getMin()  {return min;}
97float AvgStd::getMax() {return max;}
98
99void AvgStd::setRejectionSigma(float  sigmas){
100    r_sigma = sigmas;
101};
102    
103