node-red-nodes/function/smooth/17-smooth.js

61 lines
2.4 KiB
JavaScript

module.exports = function(RED) {
"use strict";
function SmoothNode(n) {
RED.nodes.createNode(this, n);
this.action = n.action;
this.round = n.round || false;
if (this.round == "true") { this.round = 0; }
this.count = Number(n.count);
var node = this;
var a = [];
var tot = 0;
var tot2 = 0;
var pop = 0;
var old = null;
this.on('input', function (msg) {
if (msg.hasOwnProperty("payload")) {
var n = Number(msg.payload);
if (!isNaN(n)) {
if ((node.action === "low") || (node.action === "high")) {
if (old == null) { old = n; }
old = old + (n - old) / node.count;
if (node.action === "low") { msg.payload = old; }
else { msg.payload = n - old; }
}
else {
a.push(n);
if (a.length > node.count) { pop = a.shift(); }
if (node.action === "max") {
msg.payload = Math.max.apply(Math, a);
}
if (node.action === "min") {
msg.payload = Math.min.apply(Math, a);
}
if (node.action === "mean") {
tot = tot + n - pop;
msg.payload = tot / a.length;
}
if (node.action === "sd") {
tot = tot + n - pop;
tot2 = tot2 + (n*n) - (pop * pop);
if (a.length > 1) {
msg.payload = Math.sqrt((a.length * tot2 - tot * tot)/(a.length * (a.length - 1)));
}
else { msg.payload = 0; }
}
}
if (node.round !== false) {
msg.payload = Math.round(msg.payload * Math.pow(10, node.round)) / Math.pow(10, node.round);
}
node.send(msg);
}
else { node.log("Not a number: "+msg.payload); }
} // ignore msg with no payload property.
});
}
RED.nodes.registerType("smooth", SmoothNode);
}