openwebrx-clone/htdocs/lib/Measurement.js

62 lines
1.6 KiB
JavaScript
Raw Normal View History

function Measurement() {
this.reset();
};
Measurement.prototype.add = function(v) {
this.value += v;
};
Measurement.prototype.getValue = function() {
return this.value;
};
Measurement.prototype.getElapsed = function() {
return new Date() - this.start;
};
Measurement.prototype.getRate = function() {
return this.getValue() / this.getElapsed();
};
Measurement.prototype.reset = function() {
this.value = 0;
this.start = new Date();
};
Measurement.prototype.report = function(range, interval, callback) {
return new Reporter(this, range, interval, callback);
}
function Reporter(measurement, range, interval, callback) {
this.measurement = measurement;
this.range = range;
this.samples = [];
this.callback = callback;
this.interval = setInterval(this.report.bind(this), interval);
};
Reporter.prototype.sample = function(){
this.samples.push({
timestamp: new Date(),
value: this.measurement.getValue()
});
};
Reporter.prototype.report = function(){
this.sample();
var now = new Date();
var minDate = now.getTime() - this.range;
this.samples = this.samples.filter(function(s) {
return s.timestamp.getTime() > minDate;
});
this.samples.sort(function(a, b) {
return a.timestamp - b.timestamp;
});
var oldest = this.samples[0];
var newest = this.samples[this.samples.length -1];
var elapsed = newest.timestamp - oldest.timestamp;
if (elapsed <= 0) return;
var accumulated = newest.value - oldest.value;
// we want rate per second, but our time is in milliseconds... compensate by 1000
this.callback(accumulated * 1000 / elapsed);
};