lib-datatable (v0.0.12)

A NodeJS library to manipulate an in memory table (array of arrays).

Use the library to create a Datatable object. With a Datatable you can maniuplate a two dimesional array of data. You can add and remove columns, get and set individual cell values, and convert to and from an array of Javascript objects.

Internally, all data is stored as an array of arrays. This is an array of rows, each of which is composed of an array of cell values. There is no restriction on the content of a Cell, it can be of any nativa data type (e.g. number, string) or even a complex object.

A Datatable also maintains an array of column headings (data.column_headings). Column headings are not required for the primary functions of a Datatable but are used when converting a Datatable to and from an array of Javascript or JSON objects. In such cases, a Datatable column corresponds to a field within the object.

Since the internal representation of a Datatable is an array of arrays with an optional array of column metadata, a significant amount of overhead is avoided as compared to an array of JSON objects. That is, we are storing any object field names only once as column metadata rather than repeating this information for each stored object. This makes a Datatable take up much less memory and makes it an ideal format for serialization and transmission of large data.

Getting Started

Install via NPM:

npm install @liquicode/lib-datatable

Simple Usage

Include the Datatable library in your source code

const LibDatatable = require( '@liquicode/lib-datatable' );

Create a Datatable object

let table = LibDatatable.NewDatable();		// Create an empty table with no rows or columns.
table.SetSize( 100, 5 );				// Resize the table to give it 100 rows and 5 columns.

Add some data

let counter = 0;
for( let row = 0; row < table.RowCount(); row++ )
{
	for( let col = 0; col < table.ColumnCount(); col++ )
	{
		table.SetValue( counter, row, col );
		counter++;
	}
}

Read some data

table.GetValue( 0, 0 ) === 0		// TRUE
table.GetValue( 'A1' ) === 0		// TRUE
table.GetValue( 0, 'A' ) === 0		// TRUE
table.GetValue( { row_num: 1, col_addr: 'A' } ) === 0		// TRUE

table.GetValue( 0, 1 ) === 1		// TRUE
table.GetValue( 'B1' ) === 1		// TRUE
table.GetValue( 0, 'B' ) === 1		// TRUE
table.GetValue( { row_num: 1, col_num: 2 } ) === 1		// TRUE

table.GetValue( 0, 2 ) === 2		// TRUE
table.GetValue( 'C1' ) === 2		// TRUE
table.GetValue( 0, 'C' ) === 2		// TRUE
table.GetValue( { row_index: 0, col_num: 3 } ) === 2		// TRUE

More Links

• Library Source Code
• Library Docs Site
• Library NPM Page