math-buffer - npm Package Compare versions

Comparing version 0.1.0 to 0.1.1

index.js

@@ -28,8 +28,11 @@ //add two buffers,
 
-
-
 //okay, need addShift(a, b, n)
 //a + (b<<n)
+
 var add = exports.add = function (a, b, c) {
   var l = Math.max(a.length, b.length)
+
+  if(a.length == b.length && (a[l-1] + b[l-1])>>1)
+    l ++
+
   if(!c) { c = new Buffer(l); c.fill() }
@@ -49,2 +52,3 @@ var carry = 0
 //basically the reverse of add.
+
 var subtract = exports.sub =
@@ -83,4 +87,6 @@ exports.subtract = function (a, b, c) {
   while(l--) {
-    if((a[l] || 0) !== (b[l] || 0))
-      return a[l] < b[l] ? -1 : 1
+    var x = a[l] || 0
+    var y = b[l] || 0
+    if(x !== y)
+      return x < y ? -1 : 1
   }
@@ -119,12 +125,15 @@ return 0
 //multiply, using shift + add
-var multiply =
-exports.mul =
+
+var multiply = exports.mul =
 exports.multiply = function (a, b, m) {
-  var w = new Buffer(b)
-  var l = a.length * 8, prev = 0
+  var l = a.length + b.length, prev = 0
+  var w = new Buffer(l); w.fill()
 
-  if(!m) m = new Buffer(a.length)
-  m.fill() //m must be zeros, or it will affect stuff.
+  ;(Array.isArray(b) ? new Buffer(b) : b).copy(w)
 
-  for(var i = 0; i < l; i++) {
+  if(!m) m = new Buffer(l)
+  if(a !== m) m.fill() //m must be zeros, or it will affect stuff.
+
+  var bits = l<<3
+  for(var i = 0; i < bits; i++) {
     if(getBit(a, i)) {
@@ -160,4 +169,4 @@ shift(w, i - prev, w)
 }
-var divide =
-exports.divide = function (a, b, q, r) {
+
+var divide = exports.divide = exports.div = function (a, b, q, r) {
   if(!q) q = new Buffer(a.length)
@@ -169,3 +178,3 @@ if(!r) r = new Buffer(a.length)
     q.fill()
-    r.copy(a) //remainder is the same
+    ;(Array.isArray(r) ? new Buffer(r) : r).copy(a) //remainder is the same
     return {quotient: q, remainder: r}
@@ -179,3 +188,3 @@ }
   _b.fill()
-  a.copy(r)
+  ;(Array.isArray(a) ? new Buffer(a) : a ).copy(r)
 
@@ -189,2 +198,3 @@ //shift b to line up with a.
   // at least in sparse numbers.
+
   var bit = mA - mB
@@ -214,4 +224,4 @@ while(bit >= 0) {
 //http://en.wikipedia.org/wiki/Modular_exponentiation#Right-to-left_binary_method
-var pow =
-exports.pow =
+
+var pow = exports.pow =
 exports.power = function (base, exp, mod) {
@@ -244,2 +254,3 @@ var result = new Buffer(exp.length)
   }
+
   var shifts = 0;
@@ -263,18 +274,20 @@
   //while u is even, divide by two.
-  while (~u[0] & 1)
+  while (isEven(u)) {
     shift(u, -1, u)
+  }
 
   //From here on, u is always odd.
   do {
-       //if v is even, 2 cannot be a divisor.
-       while (~v[0] & 1) {
-           shift(v, -1, v);
-       }
-       // Now u and v are both odd.
-       // swap so that v is larger, so that we can safely subtract v - u
-       if (compare(u, v) > 0) {
-         var t = v; v = u; u = t;
-      }
-      subtract(v, u, v)
-     } while (!isZero(v));
+   //if v is even, 2 cannot be a divisor.
+   while (isEven(v)) shift(v, -1, v)
+
+   // Now u and v are both odd.
+   // swap so that v is larger, so that we can safely subtract v - u
+    if (compare(u, v) > 0) {
+      var t = v; v = u; u = t;
+    }
+    v = subtract(v, u)
+    //v is now even, because even = odd1 - odd2
+  } while (!isZero(v))
+
   //multiply by the factors of 2 we removed at line 240
@@ -281,0 +294,0 @@ return shift(u, shifts, u)

package.json

 {
   "name": "math-buffer",
   "description": "big integer math operations implemented on top of node buffers",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "homepage": "https://github.com/dominictarr/math-buffer",
@@ -12,3 +12,4 @@ "repository": {
   "devDependencies": {
-    "tape": "~2.3.2"
+    "tape": "~2.3.2",
+    "bignum": "~0.6.2"
   },
@@ -19,3 +20,22 @@ "scripts": {
   "author": "Dominic Tarr <[e-mail]> (dominictarr.com)",
-  "license": "MIT"
+  "license": "MIT",
+  "testling": {
+    "files": "test/*.js",
+    "browsers": [
+      "ie/8..latest",
+      "firefox/17..latest",
+      "firefox/nightly",
+      "chrome/22..latest",
+      "chrome/canary",
+      "opera/12..latest",
+      "opera/next",
+      "safari/5.1..latest",
+      "ipad/6.0..latest",
+      "iphone/6.0..latest",
+      "android-browser/4.2..latest"
+    ]
+  },
+  "browser": {
+    "bignum": false
+  }
 }

README.md

@@ -5,2 +5,5 @@ # math-buffer
 
+[![testling badge](https://ci.testling.com/dominictarr/math-buffer.png)](https://ci.testling.com/dominictarr/math-buffer)
+
+
 ## byte order & base
@@ -107,3 +110,3 @@
 
-### gcd: `x = inverse(a, m)`
+### inverse: `x = inverse(a, m)`
 
@@ -110,0 +113,0 @@ Calculate the [modular multiplicative inverse](http://en.wikipedia.org/wiki/Modular_multiplicative_inverse)

test/index.js

 var big = require('../')
 var tape = require('tape')
-
+var u = require('./util')
 function B () {
@@ -8,11 +8,5 @@ return new Buffer([].slice.call(arguments))
 
-function clone (a) {
-  return JSON.parse(JSON.stringify(a))
-}
+var clone = u.clone
+var equal = u.equal
 
-function equal(t, a, b, message) {
-  //clone to turn Buffers into arrays which makes deepEquals work better.
-  t.deepEqual(clone(a), clone(b), message)
-}
-
 function createTest(t, forward, reverse, mutate) {
@@ -116,4 +110,4 @@ return function (a, b, c) {
 tape('multiply - carry2', function (t) {
-  var a = new Buffer([0x00, 0x10, 0x00, 0x00])
-  var b = new Buffer([0x00, 0x10, 0x00, 0x00])
+  var a = new Buffer([0x00, 0x10])
+  var b = new Buffer([0x00, 0x10])
   var c = new Buffer([0x00, 0x00, 0x00, 0x01])
@@ -126,4 +120,4 @@ var m = new Buffer(4); m.fill()
 tape('multiply - carry3', function (t) {
-  var a = new Buffer([0x10, 0x10, 0, 0])
-  var b = new Buffer([0x10, 0x10, 0, 0])
+  var a = new Buffer([0x10, 0x10])
+  var b = new Buffer([0x10, 0x10])
   var c = new Buffer([0x00, 0x01, 0x02, 0x01])
@@ -137,4 +131,4 @@ var m = new Buffer(4); m.fill()
 tape('multiply - carry3', function (t) {
-  var a = new Buffer([0x12, 0x34, 0, 0])
-  var b = new Buffer([0x56, 0x78, 0, 0])
+  var a = new Buffer([0x12, 0x34])
+  var b = new Buffer([0x56, 0x78])
   var c = new Buffer([0x0c, 0xee, 0x79, 0x18])
@@ -141,0 +135,0 @@ var m = new Buffer(4); m.fill()

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Fixed alerts

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Improved metrics

Total package byte prevSize

347217

increased by1073.82%

Number of package files

25

increased by150%

Lines of code

6318

increased by805.16%

Number of lines in readme file

126

increased by2.44%

Worsened metrics

Dev dependency count

2

increased by100%

Number of low supply chain risk alerts

2

increased byInfinity%

Number of medium supply chain risk alerts

1

increased byInfinity%

No dependency changes