first commit

Software/NodeJS/libs/sensors/loudnessAnalogSensor.js

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+var AnalogSensor = require('./base/analogSensor')
+
+//same class can be used for the sound sensor
+function LoudnessAnalogSensor(pin, samplespersecond) {
+    AnalogSensor.apply(this, Array.prototype.slice.call(arguments))
+    this.samplespersecond = samplespersecond || 5
+    this.results = new Array()
+}
+LoudnessAnalogSensor.prototype = new AnalogSensor()
+
+//returns loudness average and max for values taken since the last time it was called
+LoudnessAnalogSensor.prototype.readAvgMax = function () {
+    if (this.results.length == 0)
+        throw new Error('no results. Did you call start()?')
+
+    //reduce values to get the sum
+    let sum = this.results.reduce((acc, cur) => acc + cur, 0)
+    let avg = sum / this.results.length
+
+    //reduce the values to get the max
+    let max = this.results.reduce(function (a, b) {
+        return Math.max(a, b)
+    })
+
+    //reset the array - clear its elements
+    this.results = new Array()
+
+    return {
+        avg,
+        max
+    }
+}
+
+LoudnessAnalogSensor.prototype.start = function () {
+    loop.bind(this)() //so we can use 'this' inside the loop method
+    setInterval(loop.bind(this), 1000 / this.samplespersecond)
+}
+
+LoudnessAnalogSensor.prototype.stop = function () {
+    clearInterval(loop)
+}
+
+function loop() {
+    let currentResult = this.read()
+    this.results.push(currentResult)
+}
+
+module.exports = LoudnessAnalogSensor