@mitchallen/grid-core
Grid core
Installation
You must use npm 2.7.0 or higher because of the scoped package name.
$ npm init
$ npm install @mitchallen/grid-core --save
Usage
Create a new folder and do the following at the command line:
$ npm init
$ npm install @mitchallen/grid-core --save
In the same folder create a file called index.js with the content below:
"use strict";
var gridFactory = require("@mitchallen/grid-core");
var rows = 5;
var grid = gridFactory.create( { rows: rows } );
if(!grid) {
console.error("couldn't create grid");
}
var i = rows - 1,
j = 3,
value = 999;
if(! grid.set( i, j, value )) {
console.error("couldn't set grid value");
}
grid.log();
if(! grid.isCell( i, j ) ) {
console.error("parameters not within grid");
}
let result = grid.get( i, j );
if(! result) {
console.error("couldn't get grid value");
} else {
console.log("grid value: ", result );
}At the command line, execute the following:
$ node index.js
Output:
size: 5:
[ [], [], [], [], [ , , , 999 ] ]
grid value: 999
An example similar to this exists on the examples folder out on the repo.
Browser Usage
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Grid Core Example</title>
<meta name="description" content="Grid Core Example">
<script src="https://unpkg.com/@mitchallen/grid-core@0.1.10/dist/grid-core.min.js"></script>
<script>
var factory = window.MitchAllen.GridCore;
console.log(factory);
var rows = 5;
var gc = factory.create( { rows: rows } );
gc.set(rows-1,6,"alpha");
console.log(gc);
gc.log();
</script>
</head>
<body>
<h1>Grid Core Example</h1>
<p>See JavaScript developer console for output.</p>
</body>
</html>Methods
create( spec )
Factory method that returns a sparse grid object.
It takes one spec parameter that must be an object with a rows value specifying the size of the number of rows in the grid.
You can call create multiple times to create multiple grids.
var gridFactory = require("@mitchallen/grid-core");
var grid1 = gridFactory.create( { rows: 5 } );
var grid2 = gridFactory.create( { rows: 10 } );
if(!grid1 || !grid2) ...
rows
Returns the number for rows in the grid.
grid.rows.should.eql(5);
rowsSize(rowId)
Returns the number of items in the array in row rowId.
grid.rowSize(3).should.eql(10);
A row size is determined by the highest zero-based position inserted into that row.
grid.isCell( row, pos )
The row and pos parameters should be zero-based coordinates ranging from zero (0) to axis size minus one.
The method is called internally by get.
if(! grid.isCell( i, j ) ) {
console.error("parameters not within grid");
}
grid.set( row, pos, value )
The row and pos values must be greater than zero. If the parameters fail validation then a value of false is returned. Otherwise true is returned.
The value parameter can be a number, a string or even an object.
if(! grid.set( i, j, value )) {
console.error("couldn't set grid value");
}
Only the row needs to exist. If the position in the row does not exist it will be created.
grid.get( row, pos )
The row and pos values are passed to the isCell method internally for validation. If the parameters fail validation then a null object is returned. Otherwise the value of the cell (grid location) is returned.
The returned value can be a number, a string or even an object.
let result = grid.get( i, j );
if(! result) {
console.error("couldn't get grid value");
} else {
console.log("grid value: ", result );
}
grid.fill(value)
Fills the grid with whatever is passed in as value. Value can be a number, a string or even an object. Any existing values in the grid will be replaced with the new fill value.
let fillValue = "foo";
var result = grid.fill(fillValue);
grid.cloneArray()
Returns a clone of the internal array. This is not a reference. So changes to the cloned array should not change the original.
let tX = 0;
let tY = 0;
let gridValue = 100;
let cloneValue = 500;
// Set a value in the original grid
grid.set(tX,tY,gridValue);
// Clone the grid
let arr = grid.cloneArray();
// Verify value exists in clone
arr[tX][tY].should.eql(gridValue);
// Change value in clone
arr[tX][tY] = cloneValue;
// Verify new value is set in clone
arr[tX][tY].should.eql(cloneValue);
// Ensure that value does not alter original grid
grid.get(tX,tY).should.eql(gridValue);
grid.log()
Logs the size and contents of the internal array.
grid.log();
Example output:
size: 5:
[
[],
[],
[],
[],
[ , , , 999 ] ]
Testing
To test, go to the root folder and type (sans $):
$ npm test
Repo(s)
Contributing
In lieu of a formal style guide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code.
Version History
Version 0.1.9
- updated .npmignore
- updated client dist version
Version 0.1.8
- added test cases for 100% code coverage
Version 0.1.7
- updated badge links
Version 0.1.6
- changed license to MIT
- integrated travis-ci and codecov.io
- added badges to readme
Version 0.1.5
- removed unused dependency
Version 0.1.4
- added examples
Version 0.1.3
- Removed dist from .npmignore
Version 0.1.2
- fixed browserify standalone setting
- used window.MitchAllen.GridCore to access from the browser
Version 0.1.1
- removed obsolete file
Version 0.1.0
- initial release