Ask HN: How to generate topics from a question(like what Quora doing)?

This SO had helped me solve a similar problem in the past.<p><a href="https:&#x2F;&#x2F;datascience.stackexchange.com&#x2F;a&#x2F;7000" rel="nofollow">https:&#x2F;&#x2F;datascience.stackexchange.com&#x2F;a&#x2F;7000</a><p><a href="https:&#x2F;&#x2F;www.kaggle.com&#x2F;c&#x2F;facebook-recruiting-iii-keyword-extraction&#x2F;forums&#x2F;t&#x2F;6650&#x2F;share-your-approach" rel="nofollow">https:&#x2F;&#x2F;www.kaggle.com&#x2F;c&#x2F;facebook-recruiting-iii-keyword-ext...</a>

Here is a brief overview of what you need to do:<p>1. Use nltk to get all the nouns etc. from the topic.<p>2. You can use LDA&#x2F;TF-IDF (gensim) for your questions to extract the most common topic.<p>3. Use cosine similarity once you have the corpus built to tag a question to the right category.<p>Look into gensim for more details for the topic modeling.