const float GAMMA = 0.7;
const float RL10 = 15;
int analogValue;
float voltage,resistance,lux;
void setup() {
  Serial.begin(9600);
}

void loop() {
// Convert the analog value into lux value:
int analogValue = analogRead(A0);
float voltage = analogValue / 1024. * 5;
float resistance = 2000 * voltage / (1 - voltage / 5);
float lux = pow(RL10 * 1e3 * pow(10, GAMMA) / resistance, (1 / GAMMA));
 Serial.print("ความส่องสว่าง" );
 Serial.print(lux);
 Serial.print(" lux");
 delay(500);
}