sparse-array - npm Package Compare versions

Comparing version 1.2.1 to 1.3.0

index.js

@@ -12,4 +12,5 @@ 'use strict'
     this._data = []
-    this._changed = false
     this._length = 0
+    this._changedLength = false
+    this._changedData = false
   }
@@ -25,11 +26,17 @@
         this._unsetBit(index)
+        this._changedLength = true
+        this._changedData = true
       }
     } else {
+      let needsSort = false
       if (pos === -1) {
         pos = this._data.length
         this._setBit(index)
+        this._changedData = true
+      } else {
+        needsSort = true
       }
-      this._setInternalPos(pos, index, value)
+      this._setInternalPos(pos, index, value, needsSort)
+      this._changedLength = true
     }
-    this._changed = true
   }
@@ -46,2 +53,3 @@
     }
+    this._sortData()
     return this._data[pos][1]
@@ -56,6 +64,7 @@ }
   get length () {
-    if (this._changed) {
+    this._sortData()
+    if (this._changedLength) {
       const last = this._data[this._data.length - 1]
       this._length = last ? last[0] + 1 : 0
-      this._changed = false
+      this._changedLength = false
     }
@@ -142,5 +151,27 @@ return this._length
 
-  _setInternalPos(pos, index, elem) {
-    this._data[pos] = [index, elem]
-    this._data.sort(sortInternal)
+  _setInternalPos(pos, index, value, needsSort) {
+    const data =this._data
+    const elem = [index, value]
+    if (needsSort) {
+      this._sortData()
+      data[pos] = elem
+    } else {
+      // new element. just shove it into the array
+      // but be nice about where we shove it
+      // in order to make sorting it later easier
+      if (data.length) {
+        if (data[data.length - 1][0] >= index) {
+          data.push(elem)
+        } else if (data[0][0] <= index) {
+          data.unshift(elem)
+        } else {
+          const randomIndex = Math.round(data.length / 2)
+          this._data = data.slice(0, randomIndex).concat(elem).concat(data.slice(randomIndex))
+        }
+      } else {
+        this._data.push(elem)
+      }
+      this._changedData = true
+      this._changedLength = true
+    }
   }
@@ -151,2 +182,54 @@
   }
+
+  _sortData () {
+    if (this._changedData) {
+      this._data.sort(sortInternal)
+    }
+  }
+
+  bitField () {
+    const bytes = []
+    let pendingBitsForResultingByte = 8
+    let pendingBitsForNewByte = 0
+    let resultingByte = 0
+    let newByte
+    const pending = this._bitArrays.slice()
+    while (pending.length || pendingBitsForNewByte) {
+      if (pendingBitsForNewByte === 0) {
+        newByte = pending.shift()
+        pendingBitsForNewByte = 7
+      }
+
+      const usingBits = Math.min(pendingBitsForNewByte, pendingBitsForResultingByte)
+      const mask = ~(0b11111111 << usingBits)
+      const masked = newByte & mask
+      resultingByte |= masked << (8 - pendingBitsForResultingByte)
+      newByte = newByte >>> usingBits
+      pendingBitsForNewByte -= usingBits
+      pendingBitsForResultingByte -= usingBits
+
+      if (!pendingBitsForResultingByte || (!pendingBitsForNewByte && !pending.length)) {
+        bytes.push(resultingByte)
+        resultingByte = 0
+        pendingBitsForResultingByte = 8
+      }
+    }
+
+    // remove trailing zeroes
+    for(var i = bytes.length - 1; i > 0; i--) {
+      const value = bytes[i]
+      if (value === 0) {
+        bytes.pop()
+      } else {
+        break
+      }
+    }
+
+    return bytes
+  }
+
+  compactArray () {
+    this._sortData()
+    return this._data.map(valueOnly)
+  }
 }
@@ -167,2 +250,6 @@
   return a[0] - b[0]
+}
+
+function valueOnly (elem) {
+  return elem[1]
 }

package.json

 {
   "name": "sparse-array",
-  "version": "1.2.1",
+  "version": "1.3.0",
   "description": "Sparse array implementation in JS with no dependencies",
@@ -5,0 +5,0 @@ "main": "index.js",

README.md

@@ -15,3 +15,3 @@ # sparse-array
 
-Create:
+### Create:
 
@@ -23,3 +23,3 @@ ```js
 
-Set, get and unset:
+### Set, get and unset:
 
@@ -37,3 +37,3 @@ ```js
 
-Iterate:
+### Iterate:
 
@@ -54,3 +54,3 @@ ```js
 
-Find:
+### Find:
 
@@ -61,5 +61,18 @@ ```js
 
+### Internal representation:
 
+#### Bit field:
+
+```js
+const bitField = arr.bitField()
+```
+
+#### Compact array:
+
+```js
+const compacted = arr.compactArray()
+```
+
 ## License
 
 ISC

No alert changes

Improved metrics

Total package byte prevSize

13500

increased by46.61%

Number of package files

11

increased by22.22%

Lines of code

479

increased by46.93%

Number of lines in readme file

73

increased by21.67%

No dependency changes