//DHT 22 Temperature and Relative Humidity Reading Function

//Definitions
#define DHTTYPE DHT22         //1
const int DHTPIN = 15;        //2

//Libraries & Objects
#include <DHT.h>              //3

DHT dht(DHTPIN, DHTTYPE);     //4

//Variable Declaration/Initialization
float dht22AirTem = 0;        //5
float dht22AirTemSum = 0;     
String dht22Temperature = ""; 

float dht22RelHum = 0;        
float dht22RelHumSum = 0;     
String dht22Humidity = "";    

void setup()
{
  delay(5000);                //6
  
  Serial.begin(115200);       //7
  Serial.println("Measurement is starting ...");
}

void loop()
{
  Serial.println("Measuring ...");
  measureDHTTemHum(5);                                               //8
  Serial.println("Temperature:       " + dht22Temperature + " °C");  //9
  Serial.println("Relative Humidity: " + dht22Humidity + " %");
  Serial.println("==============================");
  delay(2000);                                                       //10
}

void measureDHTTemHum (byte AveragingNumber)                         //11
{
  delay(1000);                                                       //12
  dht.begin();                                                       //13
  
  dht22AirTemSum = 0;                                                //14
  dht22RelHumSum = 0;
  dht22Temperature = "";
  dht22Humidity = "";
  for (byte i = 0; i < AveragingNumber; i++)                         //15
  {
    do {                                                             //16
      dht22AirTem = dht.readTemperature();                           //17
      dht22RelHum = dht.readHumidity();                 
      if (!isnan(dht22AirTem) && !isnan(dht22RelHum))                //18
      {
        dht22AirTemSum += dht22AirTem;                               //19
        dht22RelHumSum += dht22RelHum;
      }
      else
        delay(2000);                                                 //20
    } while (isnan(dht22AirTem) || isnan(dht22RelHum));              //21
    if (i < (AveragingNumber - 1))                                   //22
      delay(2000);
  }
  dht22AirTem = dht22AirTemSum / AveragingNumber;                    //23
  if(dht22AirTem<10)                                                 //24
    dht22Temperature = '0';
  dht22Temperature = dht22Temperature + dht22AirTem;                 //25
  
  dht22RelHum = dht22RelHumSum / AveragingNumber;
  if(dht22RelHum<10)
    dht22Humidity = '0';
  dht22Humidity = dht22Humidity + dht22RelHum;
}