#define vref 4.9
void setup(){

    Serial.begin(9600);

}

void loop()
{
    int sensorValue;
    long  sum=0;
    for(int i=0;i<10;i++)// accumulate readings for 1024 times
    {
        sensorValue=analogRead(A0);
        sum=sensorValue+sum;
    //    delay(2);
    }
    long meanVal = sum/10;  // get mean value
    float vout=meanVal*vref;
    Serial.print("vout is :");
    Serial.print(vout,2);
    Serial.print("\n");
    if(vout<=90)
    {
    Serial.print("The current UV index is:");
    Serial.println(0);// get a detailed calculating expression for UV index in schematic files.
    //Serial.print("\n");
    }
    else
    {
    Serial.print("The current UV index is:");
    Serial.println(1E-06*vout*vout+0.008*vout-0.715,2);// get a detailed calculating expression for UV index in schematic files.
  //  Serial.print("\n");
    }
    delay(1000);

}