Intial Commit

nodered/rootfs/data/node_modules/fraction.js/examples/integrate.js

@@ -0,0 +1,68 @@
+/**
+ * @license Fraction.js v2.7.0 01/06/2015
+ * http://www.xarg.org/2014/03/rational-numbers-in-javascript/
+ *
+ * Copyright (c) 2015, Robert Eisele (robert@xarg.org)
+ * Dual licensed under the MIT or GPL Version 2 licenses.
+ **/
+
+// NOTE: This is a nice example, but a stable version of this is served with Polynomial.js: 
+// https://github.com/infusion/Polynomial.js
+
+var Fraction = require('../fraction.min.js');
+
+function integrate(poly) {
+
+    poly = poly.replace(/\s+/g, "");
+
+    var regex = /(\([+-]?[0-9/]+\)|[+-]?[0-9/]+)x(?:\^(\([+-]?[0-9/]+\)|[+-]?[0-9]+))?/g;
+    var arr;
+    var res = {};
+    while (null !== (arr = regex.exec(poly))) {
+
+        var a = (arr[1] || "1").replace("(", "").replace(")", "").split("/");
+        var b = (arr[2] || "1").replace("(", "").replace(")", "").split("/");
+
+        var exp = new Fraction(b).add(1);
+        var key = "" + exp;
+
+        if (res[key] !== undefined) {
+            res[key] = {x: new Fraction(a).div(exp).add(res[key].x), e: exp};
+        } else {
+            res[key] = {x: new Fraction(a).div(exp), e: exp};
+        }
+    }
+
+    var str = "";
+    var c = 0;
+    for (var i in res) {
+        if (res[i].x.s !== -1 && c > 0) {
+            str += ("+");
+        } else if (res[i].x.s === -1) {
+            str += ("-");
+        }
+        if (res[i].x.n / res[i].x.d !== 1) {
+            if (res[i].x.d !== 1) {
+                str += ("" + res[i].x.n + "/" + res[i].x.d + "");
+            } else {
+                str += ("" + res[i].x.n);
+            }
+        }
+        str += ("x");
+        if (res[i].e.n / res[i].e.d !== 1) {
+            str += ("^");
+            if (res[i].e.d !== 1) {
+                str += ("(" + res[i].e.n + "/" + res[i].e.d + ")");
+            } else {
+                str += ("" + res[i].e.n);
+            }
+        }
+        c++;
+    }
+    return str;
+}
+
+var poly = "-2/3x^3-2x^2+3x+8x^3-1/3x^(4/8)";
+
+console.log("f(x): " + poly);
+console.log("F(x): " + integrate(poly));