ASCII Function Graphs

Easily draw function graphs via NodeJS in Terminal.

Constructor

new FunctionGraph (options)

options is an object containing the following fields:

• height: the height of the graph (default: 40)
• width: the width of the graph (default: 60)
• center an object containing:
  • x: the x origin (default: width / 2)
  • y: the y origin (default: height / 2)
• marks an object containing:
  • hAxis: the character for drawing horizontal axis (default '-')
  • vAxis: the character for drawing vertical axis (default '|')
  • center: the character for axis intersection (default '+')
  • point: the character for drawing points (default '#')

Methods

addPoint (x, y)

x and y are the coordinates of the new point that will be added

toString()

Returns the stringified graph.

Example

// dependencies
var FunctionGraph = require("function-graph");

/**
 *  We will print the graph for this function.
 *
 */
function foo (x) {
    return Math.sin(x);
}


// create a new function graph
var graph = new FunctionGraph ({
    height: 30
  , width: 60
  , marks: {
        hAxis: '─'
      , vAxis: '│'
      , center: '┼'
      , point: '•'
  }
});

// for [-25, 48) add points
for (var i = -25; i < 48; i += 0.001) {
    graph.addPoint(i * 2, 5 * foo(i));
}

console.log("Below you will see the sinus graph:")
// output graph
console.log(graph.toString());

How to test

$ npm install function-graph
$ cd node_modules/function-graph
$ npm test

> [email protected] test /home/.../function-graph
> node test/1.js

Below you will see the sinus graph:
                              ^
                              │
                              │
                              │
                              │
                              │
                              │
                              │
                              │
                              │
                              │
       ••••         •••       │••••         •••         ••••
       •  •        •• ••      │•  •        •• ••        •  •
      ••  ••       •   •      ••  ••       •   ••      ••
      •    •      ••   ••     •    •      ••    •      •
─────••────••─────•─────••────•────••─────•─────••────••───>
•    •      •    ••      •    •     ••   ••      •    •
•   ••      ••   •       ••  ••      •   •       ••  ••
••  •        •• ••        •  •│      •• ••        •  •
 ••••         •••         ••••│       •••         ••••
                              │
                              │
                              │
                              │
                              │
                              │
                              │
                              │
                              │
                              │

Changelog

• 0.1.2

  • better example
  • added comments

• 0.1.1

  • Added options.marks setting (#4)

• 0.1.0

  Initial release

License

See the LICENSE file.