added continuing fractions

Author: shadowcodex

index.js

@@ -5,4 +5,5 @@ exports.inefficient = require('./modules/sorts/inefficient.js');
 exports.simple = require('./modules/sorts/simple.js');
 exports.other = require('./modules/sorts/other.js');
 exports.Stack = require('./modules/data-types/stack.js');
-exports.isPrime = require('./modules/algorithms/is-prime.js');
+exports.isPrime = require('./modules/algorithms/is-prime.js');
+exports.continuingFraction = require('./modules/algorithms/continuing-fraction.js');

modules/algorithms/continuing-fraction.js

@@ -0,0 +1,43 @@
+
+var decimal = z =>{
+    var d = 0
+    while(z.length){
+        d=1/(d+z.pop())
+    }
+    return d;
+}
+
+var reducedFraction = z => {
+    var d = decimal(z);
+    var e = 1.0E-15
+    var h, f, j, k, l, m, a, x
+    x = d
+    a = ~~x
+    f = 1
+    l = 0
+    h = a
+    k = 1
+    while (x-a > e*k*k) {
+        x = 1/(x-a)
+        a = ~~x
+        j = f 
+        f = h
+        m = l
+        l = k
+        h = j + a*f
+        k = m + a*l
+    }
+    return h+'/'+k
+}
+
+var product = z => {
+    var rf = reducedFraction(z);
+    rf = rf.split('/');
+    return rf[0] * rf[1];
+}
+
+module.exports = {
+    'product': product,
+    'reducedFraction': reducedFraction,
+    'decimal': decimal
+};

modules/algorithms/readme.md

@@ -7,3 +7,10 @@ Various algorithms developed for different purposes. Some are standard, some are
 * isPrime(number) ![status](https://img.shields.io/badge/status-completed-brightgreen.svg)
   * *This checks to see if the number passed to it is prime.*
 
+* continuingFraction ![status](https://img.shields.io/badge/status-completed-brightgreen.svg)
+  * decimal
+    * *This takes an array of integers and returns the results of running them as a continuing fraction. Returns as decimal number.*
+  * reducedFraction
+    * *This takes an array of integers and returns the results of running them as a continuing fraction. Returns as a reduced fraction number.*
+  * product
+    * *This takes an array of integers and returns the results of running them as a continuing fraction. Returns the product of the numerator and the denominator of the reduced fraction.*

test/simpletest.js

@@ -21,6 +21,8 @@ var x = [1,5,7,2,43,6,26,7,2356,7,346,1,42,0];
 // console.log(theStack.pop());
 // console.log(theStack.pop());
 
-for(var i=0; i < x.length; i++){
-    console.log(dt.isPrime(x[i]), x[i]);    
-}
+// for(var i=0; i < x.length; i++){
+//     console.log(dt.isPrime(x[i]), x[i]);    
+// }
+
+//console.log(dt.continuingFraction.decimal(x));