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

64 lines
2.3 KiB
JavaScript

/**
* Copyright 2014 IBM Corp.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
**/
module.exports = function(RED) {
"use strict";
function SmoothNode(n) {
RED.nodes.createNode(this, n);
this.action = n.action;
this.round = n.round || false;
this.count = Number(n.count);
var node = this;
var a = [];
var tot = 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.round) { msg.payload = Math.round(msg.payload); }
node.send(msg);
}
else { node.log("Not a number: "+msg.payload); }
} // ignore msg with no payload property.
});
}
RED.nodes.registerType("smooth", SmoothNode);
}