Are there any machine learning libraries in C#? I'm after something like WEKA. Thank you.
Check out this awesome list on GitHub. Of the frameworks listed, Accord.NET is open-source and the most popular with over 2,000 stars.
Also, check out the official machine learning library for .NET provided by Microsoft: https://github.com/dotnet/machinelearning
OLD
There's a neural network library called AForge.net on the codeproject. (Code hosted at Google code) (Also checkout the AForge homepage - According to the homepage, the new version now supports genetic algorithms and machine learning as well. It looks like it's progressed a lot since I last played with it)
I don't know it's it's anything like WEKA as I've never used that.
(there's also an article on it's usage)