Updated original april_temp_sensor to remove use of deprecated methods, to remove the use of pin2 for activating the lamp, and to use CSV format for communication with xively.com. Also added agent code taken from https://xively.com/dev/tutorials/electric_imp to which I have made trivial modifications.

agent

const FEED_ID = "YOUR_FEED_ID";
const API_KEY = "YOUR_API_KEY";

// Accept CSV from device, then format request to and accept response from xively.com 
device.on("data", function(feedCSV) {      
    server.log(feedCSV);
    local xively_url = "https://api.xively.com/v2/feeds/" + FEED_ID + ".csv";
    local request = http.put(xively_url, {"X-ApiKey":API_KEY, "Content-Type":"text/csv", "User-Agent":"Xively-Imp-Lib/1.0"}, feedCSV);
    local response = request.sendsync();
    if(response.statuscode != 200) {
        server.log("error code '" + response.statuscode + "' sending request: "+request);
    }
});

april_temp_sensor

hardware.pin1.configure(ANALOG_IN);
 
function update_temp() {
  // keep the imp awake
  imp.wakeup(10, update_temp);
  
  // get the raw voltage value from temp sensor btw 0-65535
  // in this case that needs mapping to the range 0-3.3v
  local reading = hardware.pin1.read();
  
  // get the ratio 
  local ratio = 65535.0 / reading;
  
  // make units milivolts and get voltage we can work with
  //voltage = (hardware.voltage() * 1000) / divider;
  local voltage = 3300 / ratio;
  
  // get temperature in degrees Celsius
  local temperatureC = (voltage - 500) / 10.0;
  
  // convert to degrees Farenheit
  local temperatureF = (temperatureC * 9.0 / 5.0) + 32.0;
  
  server.log("temp: " + temperatureF);
  
  // format our output as comma separated name value pair
  local csv = "temp," + temperatureF;
  
  agent.send("data", csv);
}
 
update_temp();