Hi!

Another option would be converting to an arrow-backed pandas table and
using a dataframe query method. Other libraries like DuckDB most
likely offer similar options.

BR

J

czw., 29 sie 2024 o 02:54 Felipe Oliveira Carvalho
<[email protected]> napisał(a):
>
> You can build `compure::Expression` instances [1] and use them in different 
> contexts like scanning datasets [2] and producing Substrait plans [3] that 
> you can execute.
>
> But you have to write your own parser and define the scope and semantics of 
> the operations you would support.
>
> [1] 
> https://github.com/apache/arrow/blob/main/cpp/src/arrow/compute/expression.h#L45
> [2] 
> https://github.com/apache/arrow/blob/main/cpp/examples/arrow/dataset_documentation_example.cc#L266
> [3] 
> https://github.com/apache/arrow/blob/main/cpp/src/arrow/engine/substrait/relation.h#L55
>
> --
> Felipe
>
> On Wed, Aug 28, 2024 at 1:11 AM Surya Kiran Gullapalli 
> <[email protected]> wrote:
>>
>> Hello all,
>> Let's say I've a table containing 3 columns 'A', 'B', and 'C'. Is it 
>> possible to create a 4th column 'D' using a formula (like (A+B)/C) ?
>>
>> I know I can manually create them using compute functions, but is it 
>> possible to parse a formula like the above and compute the column on the fly 
>> at runtime ?
>>
>> Any pointers are greatly appreciated.
>>
>> Thanks,
>> Surya

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