Introduction

Quark is framework built on top of Linkurious.js which lets you painlessly visualize your data in form of nodes & edges. It offers a lot of features out of the box and runs in a browser so you don't need to worry about installing anything or configuring things. Just feed it some data and Quark will plot a beautiful and intractable graph out of it.
Here's a screenshot if you are eager to take a look at it:

Browser Support

All modern web browsers are supported, including:

• Internet Explorer 10+
• Chrome 23+ and Chromium
• Firefox 15+
• Safari 6+

Touch events on tablet and mobile are currently supported as beta features.

Usage

In-Graph Controls

• left click Select a node
• right click Highlight edges of the node
• drag Move around
• mousewheel zoom in & zoom out

Keyboard Controls

• Keyboard Arrows Move around
• spacebar + + Zoom in
• spacebar + - Zoom out
• spacebar + a Select/deselect all nodes
• spacebar + e Select neighbors of selected node(s)
• spacebar + u Deselect nodes
• spacebar + i Select nodes with no edges
• spacebar + l Select nodes with 1 edge

Features

Options in the sidebar are divided in sections and their documentation here follows the same style.

Circle

It arranges the nodes in a circular layout.

Center

Click a node and then click on the center option to place it in the center of the graph.

Decolor

It resets the color of all edges and nodes.

Lasso

Lasso tool lets you select nodes by drawing a line around them.

Stabilize

It optimizes the size of nodes that are too small or too big.

Clean

It removes nodes & edges which are too small.

Delete

It deletes the selected node(s) from the graph.

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Edge Style (Dropdown)

The dropdown list lets you select different types of edge styles.
Supported edge styles are:

• line Simple straight lines
• Curved Curved lines
• Arrow Arrows that point towards the target of the edge
• cArrows Arrows but curved

Edges {int}

It shows the total number of edges. You can click it to toggle edges on/off.

Nodes {int}

It shows the total number of nodes. You can click it to toggle nodes on/off.

Edge labels

Toggle edge labels on/off.

Node labels

Toggle node labels on/off.

Color

The color option lets you choose a color from a color picker and apply it to the selected node(s).

Find

Enter full label/id of a node and it will find and highlight it. Default color is yellow.

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Make/Color Clusters

It helps you find & color nodes that are more densely connected together than to the rest of the network.

Level (Dropdown)

It lets you select the "aggressiveness" to use while coloring the communities. Lower the level, higher the number of communities.

Reset

It simply resets the color change made by the cluster option. However it doesn't reset the the position of the nodes i.e. they remain in cluster form.

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Export to JSON

As the name suggests, it lets you export your current graph to a JSON file.

How to load a graph?

Before reading any further, take a look at my Orbit which uses Quark to analyse crypto wallet relationships.

Scenario 1

You have 5 points a, b, c, d, e and you know the relationships between them like a is related to c. Then create a file with the contents

a,e
c,d
e,a
d,e
a,c
c,e

Save it with any name and any extension and feed it to quark.py as follows python3 quark.py <filename> That's it! Open quark.html and you will see your graph.

Result

Why are the nodes so small? Because in this automatic mode, the size of a node is determined by how many other nodes are connected to. For any noticeable variation in node size, your graph should have enough nodes i.e. larger than 20.

Scenario 2

If you are like me and you want full control of everything like the co-ordinates and size of nodes, edge thickness and their labels etc. then you will need to arrange this information in JSON syntax as follows:

{
"nodes": [{"label": "a", "x": 1, "y": 1, "id": "node1", "size":10}, {"label": "b", "x": 2, "y": 1, "id": "node2", "size":4}],
"edges": [{"source":"node1", "target":"node2", "id":"edge1", "size":2}]
}

Save it with any name and again, pass it to the handler and open quark.html

Result

Performance

Quark is tested and built on a spaghetti laptop with just 3GB RAM, built-in graphic card & i3 processor. On this configuration, a graph with 7000 nodes & 3000 edges was rendering just fine.
A computer with better specifications will be able to handle more data smoothly. Just to be on the safe side, Quark prompts the user for using webgl renderer if the number of edges is more than 8000.
webgl uses your GPU to render graphs which boosts the performance but it doesn't support interaction events. Quark uses canvas renderer by default.

Tips:

• Edges consume more memory than nodes.
• Memory caused by edge styles: line < curve < arrow < curved arrow
• Delete the nodes which seem insignificant to you.
• Hide edges/nodes when you are not dealing with them.
• Hide node labels (you will still be able to see them on hovering over nodes).
• Hide edge labels.

Contribution

Quark is built on top of Linkurious.js and the files from Linkurious.js are stored in the libs directory. The bugs in them are out of scope so don't open an issue here. You are welcome if you want to fix issues yourself with a pull request./ Feel free to open issues about a bug, question or feature request.