pandas dataframe O(1) index by column












0















I have a large dataframe and want to support O(1) index by one column. I tried set_index but that seems to be not that fast when using with iloc. Any thoughts on how to speed this up?






python pandas







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  • 4





    Not sure what you mean by support O(1) index by one column

    – RafaelC
    Nov 20 '18 at 1:25











  • Pandas indices are effectively hash tables. pd.Index can only contain hashable items. One way to get a bit more speedup is by making sure the index doesn't contain duplicates. I believe the getitem lookup is O(1) when both of those conditions are satisfied

    – Brad Solomon
    Nov 20 '18 at 2:07


















0















I have a large dataframe and want to support O(1) index by one column. I tried set_index but that seems to be not that fast when using with iloc. Any thoughts on how to speed this up?






python pandas







share|improve this question


















  • 4





    Not sure what you mean by support O(1) index by one column

    – RafaelC
    Nov 20 '18 at 1:25











  • Pandas indices are effectively hash tables. pd.Index can only contain hashable items. One way to get a bit more speedup is by making sure the index doesn't contain duplicates. I believe the getitem lookup is O(1) when both of those conditions are satisfied

    – Brad Solomon
    Nov 20 '18 at 2:07
















0












0








0








I have a large dataframe and want to support O(1) index by one column. I tried set_index but that seems to be not that fast when using with iloc. Any thoughts on how to speed this up?






python pandas







share|improve this question














I have a large dataframe and want to support O(1) index by one column. I tried set_index but that seems to be not that fast when using with iloc. Any thoughts on how to speed this up?






python pandas




python pandas






share|improve this question













share|improve this question











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asked Nov 20 '18 at 1:20









Mr.cyslMr.cysl

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  • 4





    Not sure what you mean by support O(1) index by one column

    – RafaelC
    Nov 20 '18 at 1:25











  • Pandas indices are effectively hash tables. pd.Index can only contain hashable items. One way to get a bit more speedup is by making sure the index doesn't contain duplicates. I believe the getitem lookup is O(1) when both of those conditions are satisfied

    – Brad Solomon
    Nov 20 '18 at 2:07
















  • 4





    Not sure what you mean by support O(1) index by one column

    – RafaelC
    Nov 20 '18 at 1:25











  • Pandas indices are effectively hash tables. pd.Index can only contain hashable items. One way to get a bit more speedup is by making sure the index doesn't contain duplicates. I believe the getitem lookup is O(1) when both of those conditions are satisfied

    – Brad Solomon
    Nov 20 '18 at 2:07










4




4





Not sure what you mean by support O(1) index by one column

– RafaelC
Nov 20 '18 at 1:25





Not sure what you mean by support O(1) index by one column

– RafaelC
Nov 20 '18 at 1:25













Pandas indices are effectively hash tables. pd.Index can only contain hashable items. One way to get a bit more speedup is by making sure the index doesn't contain duplicates. I believe the getitem lookup is O(1) when both of those conditions are satisfied

– Brad Solomon
Nov 20 '18 at 2:07







Pandas indices are effectively hash tables. pd.Index can only contain hashable items. One way to get a bit more speedup is by making sure the index doesn't contain duplicates. I believe the getitem lookup is O(1) when both of those conditions are satisfied

– Brad Solomon
Nov 20 '18 at 2:07














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