To have a dynamic collection instead of using arrays when the total quantity is unknown
<HTML>
<HEAD>
<META NAME="GENERATOR" Content="Microsoft Visual Studio 6.0">
<TITLE></TITLE>
<Script language="JavaScript">
//////////////////////////////////////////////////////
// File: vector.js
//
// Author: Jason Geissler
//
// Date: Sept 3, 2003
//
// Purpose: To have a dynamic collection instead
// of using arrays when the total quantity
// is unknown
//////////////////////////////////////////////////////
// Vector Constructor -- constructs the object
function Vector(inc) {
if (inc == 0) {
inc = 100;
}
/* Properties */
this.data = new Array(inc);
this.increment = inc;
this.size = 0;
/* Methods */
this.getCapacity = getCapacity;
this.getSize = getSize;
this.isEmpty = isEmpty;
this.getLastElement = getLastElement;
this.getFirstElement = getFirstElement;
this.getElementAt = getElementAt;
this.addElement = addElement;
this.insertElementAt = insertElementAt;
this.removeElementAt = removeElementAt;
this.removeAllElements = removeAllElements;
this.indexOf = indexOf;
this.contains = contains
this.resize = resize;
this.toString = toString;
this.sort = sort;
this.trimToSize = trimToSize;
this.clone = clone;
this.overwriteElementAt;
}
// getCapacity() -- returns the number of elements the vector can hold
function getCapacity() {
return this.data.length;
}
// getSize() -- returns the current size of the vector
function getSize() {
return this.size;
}
// isEmpty() -- checks to see if the Vector has any elements
function isEmpty() {
return this.getSize() == 0;
}
// getLastElement() -- returns the last element
function getLastElement() {
if (this.data[this.getSize() - 1] != null) {
return this.data[this.getSize() - 1];
}
}
// getFirstElement() -- returns the first element
function getFirstElement() {
if (this.data[0] != null) {
return this.data[0];
}
}
// getElementAt() -- returns an element at a specified index
function getElementAt(i) {
try {
return this.data[i];
}
catch (e) {
return "Exception " + e + " occured when accessing " + i;
}
}
// addElement() -- adds a element at the end of the Vector
function addElement(obj) {
if(this.getSize() == this.data.length) {
this.resize();
}
this.data[this.size++] = obj;
}
// insertElementAt() -- inserts an element at a given position
function insertElementAt(obj, index) {
try {
if (this.size == this.capacity) {
this.resize();
}
for (var i=this.getSize(); i > index; i--) {
this.data[i] = this.data[i-1];
}
this.data[index] = obj;
this.size++;
}
catch (e) {
return "Invalid index " + i;
}
}
// removeElementAt() -- removes an element at a specific index
function removeElementAt(index) {
try {
var element = this.data[index];
for(var i=index; i<(this.getSize()-1); i++) {
this.data[i] = this.data[i+1];
}
this.data[getSize()-1] = null;
this.size--;
return element;
}
catch(e) {
return "Invalid index " + index;
}
}
// removeAllElements() -- removes all elements in the Vector
function removeAllElements() {
this.size = 0;
for (var i=0; i<this.data.length; i++) {
this.data[i] = null;
}
}
// indexOf() -- returns the index of a searched element
function indexOf(obj) {
for (var i=0; i<this.getSize(); i++) {
if (this.data[i] == obj) {
return i;
}
}
return -1;
}
// contains() -- returns true if the element is in the Vector, otherwise false
function contains(obj) {
for (var i=0; i<this.getSize(); i++) {
if (this.data[i] == obj) {
return true;
}
}
return false;
}
// resize() -- increases the size of the Vector
function resize() {
newData = new Array(this.data.length + this.increment);
for (var i=0; i< this.data.length; i++) {
newData[i] = this.data[i];
}
this.data = newData;
}
// trimToSize() -- trims the vector down to it's size
function trimToSize() {
var temp = new Array(this.getSize());
for (var i = 0; i < this.getSize(); i++) {
temp[i] = this.data[i];
}
this.size = temp.length - 1;
this.data = temp;
}
// sort() - sorts the collection based on a field name - f
function sort(f) {
var i, j;
var currentValue;
var currentObj;
var compareObj;
var compareValue;
for(i=1; i<this.getSize();i++) {
currentObj = this.data[i];
currentValue = currentObj[f];
j= i-1;
compareObj = this.data[j];
compareValue = compareObj[f];
while(j >=0 && compareValue > currentValue) {
this.data[j+1] = this.data[j];
j--;
if (j >=0) {
compareObj = this.data[j];
compareValue = compareObj[f];
}
}
this.data[j+1] = currentObj;
}
}
// clone() -- copies the contents of a Vector to another Vector returning the new Vector.
function clone() {
var newVector = new Vector(this.size);
for (var i=0; i<this.size; i++) {
newVector.addElement(this.data[i]);
}
return newVector;
}
// toString() -- returns a string rep. of the Vector
function toString() {
var str = "Vector Object properties:\n" +
"Increment: " + this.increment + "\n" +
"Size: " + this.size + "\n" +
"Elements:\n";
for (var i=0; i<getSize(); i++) {
for (var prop in this.data[i]) {
var obj = this.data[i];
str += "\tObject." + prop + " = " + obj[prop] + "\n";
}
}
return str;
}
// overwriteElementAt() - overwrites the element with an object at the specific index.
function overwriteElementAt(obj, index) {
this.data[index] = obj;
}
//////////////////////////////////////////////////////
// File: Matrix.js
//
// Author: Jason Geissler
//
// Date: March 9, 2004
//
// Purpose: To have a multidimensional dynamic collection instead
// of using arrays when the total quantity
// is unknown
//////////////////////////////////////////////////////
// Matrix() - object constructor
function Matrix(h, w) {
/*Properties */
this.height = h;
this.width = w;
this.rows = new Vector(w);
// set up this.rows.
for (var r = 0; r < this.height; r++) {
var theRow = new Vector(w);
for (var c = 0; c < this.width; c++) {
theRow.addElement(null);
}
this.rows.addElement(theRow);
}
/*Methods*/
this.elementAt = elementAt;
this.setElementAt = setElementAt;
this.insertRow = insertRow;
this.insertColumn = insertColumn;
this.removeRowAt = removeRowAt;
this.removeColumnAt = removeColumnAt;
this.getWidth = getWidth;
this.getHeight = getHeight;
this.toString = toString;
}
// getElementAt() - returns a value from the given row/column.
function elementAt(row, col) {
try {
var theRow = this.rows.getElementAt(row);
return theRow.getElementAt(col);
}
catch(e) {
return "Invalid index";
}
}
// setElementAt() - sets a value at a given row/column
function setElementAt(value, row, col) {
if (row < 0 || row >= this.height || col < 0 || col >= this.width) {
return "Matrix object out of Bounds";
}
var theRow = this.rows.getElementAt(row);
theRow.insertElementAt(value, col);
}
// insertRowAt() - Inserts a blank row at the end.
function insertRow() {
try {
this.height++;
var theRow = new Vector(this.width);
for (var r = 0; r < this.width; r++) {
theRow.addElement(null);
}
this.rows.insertElementAt(theRow, this.height-1);
}
catch (e) {
return "Excecption occured " + e;
}
}
// insertColumnAt() -- Inserts a column at the end.
function insertColumn() {
try {
this.width++;
for (var c=0; c < this.height; c++) {
this.rows.getElementAt(c).insertElementAt(null, this.width-1);
}
}
catch (e) {
return "Invalid column number";
}
}
// removeRowAt() - removes a row at a given index.
function removeRowAt(row) {
try {
var result = this.rows.getElementAt(row);
this.height--;
for (var r=row + 1; r <= this.height; r++) {
var theRow = this.rows.getElementAt(r);
this.rows.insertElementAt(theRow, r-1);
this.rows.removeElementAt(r);
}
return result;
}
catch (e) {
return "Invalid row number";
}
}
// removeColumnAt() - removes a given column
function removeColumnAt(col) {
try {
var result = new Vector(this.height);
this.width--;
for(var r = 0; r < this.height; r++) {
var element = this.rows.getElementAt(r).removeElementAt(col);
result.addElement(element);
}
return result;
}
catch (e) {
return "Invalid column number";
}
}
// getWidth() - returns the Matrix width
function getWidth() {
return this.width;
}
// getHeight() - returns the Matrix height
function getHeight() {
return this.height;
}
// toString() - returns String data about the Matrix object
function toString() {
var s = "Height: " + this.height + " Width: " + this.width + " Rows: " + this.rows;
return s;
}
</Script>
<Script language="JavaScript">
/*
elementAt;
setElementAt;
insertRow;
insertColumn;
removeRowAt;
removeColumnAt;
getWidth;
getHeight;
toString;
*/
var theMatrix = new Matrix(8,8);
var counter = 1;
for (var i = 0; i < theMatrix.getHeight(); i++) {
for (var j = 0; j < theMatrix.getWidth(); j++) {
if (counter % 2 == 0) {
theMatrix.setElementAt("red", i, j);
}
else {
theMatrix.setElementAt("black", i, j);
}
counter++;
}
counter++;
}
</Script>
</HEAD>
<BODY>
<Table align="center">
<TR><TD align=center colspan=8><B>Element At</TD></TR>
<Script language="JavaScript">
for (var x = 0; x < theMatrix.getHeight(); x++) {
document.write("<TR>");
for (var y = 0; y < theMatrix.getWidth(); y++) {
var color = theMatrix.elementAt(x, y);
document.write("<TD bgcolor='" + color + "'> </TD>");
}
document.write("</TR>");
}
document.writeln("");
document.writeln("");
document.writeln("<B>Width: </B>" + theMatrix.getWidth());
document.writeln("<B>Height: </B>" + theMatrix.getHeight());
document.writeln("<B>ToString: </B>" + theMatrix.toString());
</Script>
</Table>
<Table align="center">
<TR><TD align=center colspan=8><B>Remove Row At</TD></TR>
<Script language="JavaScript">
var removedRow = theMatrix.removeRowAt(2);
for (var x = 0; x < theMatrix.getHeight(); x++) {
document.write("<TR>");
for (var y = 0; y < theMatrix.getWidth(); y++) {
var color = theMatrix.elementAt(x, y)
document.write("<TD bgcolor='" + color + "'> </TD>");
}
document.write("</TR>");
}
</Script>
</Table>
</Table>
<Table align="center">
<TR><TD align=center colspan=8><B>Remove Column At</TD></TR>
<Script language="JavaScript">
var removedRow = theMatrix.removeColumnAt(2);
for (var x = 0; x < theMatrix.getHeight(); x++) {
document.write("<TR>");
for (var y = 0; y < theMatrix.getWidth(); y++) {
var color = theMatrix.elementAt(x, y)
document.write("<TD bgcolor='" + color + "'> </TD>");
}
document.write("</TR>");
}
</Script>
</Table>
</BODY>
</HTML>
Related examples in the same category