Sets

This is a online, browser-based tool that implements set operations such as union, intersect, difference on lists of things. It is implemented in Javascript.

Scratch an itch. Right?

I wanted an easy way to take a list of email addresses, de-duplicate them and remove any other names that appear on another list.

This could have been done in several tools (I used a combination of Excel and the GNU utility comm (although it was probably possible to do it all in the spreadsheet), but I wanted a single-use tool that I could pass to other people that was simple, quick enough and I could make changes to.

It could probably be used for other things, but I can't think of any right now.

So, paste a list (newline separated) into A and B (lists can be empty), pick your operator and press the button.

Recommend disabling the spell check feature of the boxes (in Firefox this is right-click and un-check 'Check Spelling') as it will slow things down.

Works on a few thousand rows, but gets slower after that.

• sort - will sort A
• unique - will determine sorted unique (de-duped) values in A
• union - will merge A and B (sorted unique)
• intersect - will show only elements in common between A and B (sorted unique)
• difference A-B - will subtract B from A (sorted unique)
• difference B-A - will subtract A from B (sorted unique)
• preserve case - will not lower input prior to operation

Your data is safe - all the operations are performed in the browser on your PC - nothing is sent to me or anyone else. (other to let me know that you've seen this page).

Um, there should also be a disclaimer here, something along the line that you use the tool at your own risk and I will not be held responsible if something bad happens. If you have a problem with this then don't use it.

Like everything on this site (other than your comments) I assert my rights of ownership and claim Copyright on it.

I'm well aware that the algorithms are sub-standard and it could be much faster with a little tweaking, but it's good enough for now.

Let me know if you use it (and what you use it for).