D3.js with force direct graph with support for drag and drop to make node fixed ( http://stackoverflow.com/questions/10899725/d3-js-force-directed-graph-with-support-for-drag-and-drop-to-make-selected-node )

graph.json

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index.html

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<h3><a href="http://stackoverflow.com/questions/10899725/d3-js-force-directed-graph-with-support-for-drag-and-drop-to-make-selected-node">http://stackoverflow.com/questions/10899725/d3-js-force-directed-graph-with-support-for-drag-and-drop-to-make-selected-node</a></h3>
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@ducksmanager :
Working as intended, node will not be positioned by the force simulation if the fixed value is set to true. As this example simple sets the dropped node fixed value to true, it get's excluded in the force layout simulation.

I guess you could easily write some code that sets neighbors 'fixed' value to false for the node you drop. So if you drop B, check neighbors for B and set it's neighbors to false.

http://jsfiddle.net/xReHA/2/ I guess would help you to determine which nodes are linked to the one your selected/dropping :-)

If I have some free time, I can probably hack together another demo which does what you want.

That would be great ! Keep me in touch : I'm not sure I would succeed in hacking the script myself ^^

Hey I am new to the data visualization world and really like your solution to a problem I am having with the force directed graph. I am not sure I understand the .json file. I would like to create one with some live data I have but do not understand the source target linking with the names can you explain how the numbers match up with the names?