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| Date | Wed, 30 Jul 2014 21:28:59 -0500 |
| Subject | Re: speed up pandas calculation |
| From | Skip Montanaro <skip.montanaro@gmail.com> |
| To | Chris Kaynor <ckaynor@zindagigames.com> |
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On Wed, Jul 30, 2014 at 8:11 PM, Chris Kaynor <ckaynor@zindagigames.com> wrote: > Another way to write this, using a list expression (untested): > new_df = [col for col in df if col.value in keep_col] As I am learning (often painfully) with pandas and JavaScript+(d3 or jQuery), loops are the enemy. You want to operate on large chunks of data simultaneously. In pandas, those chunks are thinly disguised numpy arrays. In JS+(ds or jQuery), those chunks are selections from the DOM. I should have paid closer attention to the APL unit of my programming languages survey class in college. Skip
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Re: speed up pandas calculation Skip Montanaro <skip.montanaro@gmail.com> - 2014-07-30 21:28 -0500 Re: speed up pandas calculation Rustom Mody <rustompmody@gmail.com> - 2014-07-30 19:55 -0700
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