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Johan Mabille edited comment on ARROW-602 at 3/17/17 1:57 PM: -------------------------------------------------------------- Ok, so it is possible to provide an STL compliant iterator. Cool ! EDIT: still a little problem, the value_type is unknown at compilation, so it might be usefull to add it as a template parameter of ChunkedArray. Besides, that you allows type checking in the its constructor I think most of the use cases would be to apply STL-like algorithms, so it makes sense to iterate over non-null values only. Later we can provide a "full" iteration interface for the case where iteration over null values is required, what do you think ? was (Author: johanmabille): Ok, so it is possible to provide an STL compliant iterator. Cool ! I think most of the use cases would be to apply STL-like algorithms, so it makes sense to iterate over non-null values only. Later we can provide a "full" iteration interface for the case where iteration over null values is required, what do you think ? > C++: Provide iterator access to primitive elements inside a > Column/ChunkedArray > ------------------------------------------------------------------------------- > > Key: ARROW-602 > URL: https://issues.apache.org/jira/browse/ARROW-602 > Project: Apache Arrow > Issue Type: Improvement > Components: C++ > Reporter: Uwe L. Korn > Labels: beginner, newbie > > Given a ChunkedArray, an Arrow user must currently iterate over all its > chunks and then cast them to their types to extract the primitive memory > regions to access the values. A convenient way to access the underlying > values would be to offer a function that takes a ChunkedArray and returns a > C++ iterator over all elements. > While this may not be the most performant way to access the underlying data, > it should have sufficient performance and adds a convenience layer for new > users. -- This message was sent by Atlassian JIRA (v6.3.15#6346)