int readPinAnalog = 2; //You can make up any name for your pins here
int writePinPwm = 7;
void setup()
{
   pinMode(readPinAnalog, INPUT); //stating that the phototransistor will be input
   pinMode(writePinPwm, OUTPUT); //stating that the LED will be output
}
void loop()
{ // cycle functions below
   int readAnalogValue = analogRead(readPinAnalog); //stating that the MC should read the value of pin 2
   int tmp = readAnalogValue; // storing the value of pin 2
   analogWrite(writePinPwm,tmp); //give the value as input for pin 7
   delay(100); //a new cycle every 100 ms
} // end of cycle functions