[GitHub] [arrow] aocsa commented on a change in pull request #10802: ARROW-1568: [C++] Implement Drop Null Kernel for Arrays

[GitBox <gi...@apache.org>]

aocsa commented on a change in pull request #10802:
URL: https://github.com/apache/arrow/pull/10802#discussion_r680646185



##########
File path: cpp/src/arrow/compute/kernels/vector_selection.cc
##########
@@ -2146,6 +2147,144 @@ class TakeMetaFunction : public MetaFunction {
   }
 };
 
+// ----------------------------------------------------------------------
+// DropNull Implementation
+
+Result<std::shared_ptr<arrow::Array>> GetNotNullIndices(
+    const std::shared_ptr<Array>& column, MemoryPool* memory_pool) {
+  std::shared_ptr<arrow::Array> indices;
+  arrow::NumericBuilder<arrow::Int32Type> builder(memory_pool);
+  builder.Reserve(column->length() - column->null_count());
+
+  std::vector<int32_t> values;
+  for (int64_t i = 0; i < column->length(); i++) {
+    if (column->IsValid(i)) {
+      builder.UnsafeAppend(static_cast<int32_t>(i));
+    }
+  }
+  RETURN_NOT_OK(builder.Finish(&indices));
+  return indices;
+}
+
+Result<std::shared_ptr<arrow::Array>> GetNotNullIndices(
+    const std::shared_ptr<ChunkedArray>& chunks, MemoryPool* memory_pool) {
+  std::shared_ptr<arrow::Array> indices;
+  arrow::NumericBuilder<arrow::Int32Type> builder(memory_pool);
+  builder.Reserve(chunks->length() - chunks->null_count());
+  int64_t relative_index = 0;
+  for (int64_t chunk_index = 0; chunk_index < chunks->num_chunks(); ++chunk_index) {
+    auto column_chunk = chunks->chunk(chunk_index);
+    for (int64_t col_index = 0; col_index < column_chunk->length(); col_index++) {
+      if (column_chunk->IsValid(col_index)) {
+        builder.UnsafeAppend(static_cast<int32_t>(relative_index + col_index));
+      }
+    }
+    relative_index += column_chunk->length();
+  }
+  RETURN_NOT_OK(builder.Finish(&indices));
+  return indices;
+}
+
+Result<std::shared_ptr<RecordBatch>> DropNullRecordBatch(const RecordBatch& batch,

Review comment:
       DropNullRecordBatch now uses internally GetTakeIndicesImpl and it takes into consideration the offset.  




-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: github-unsubscribe@arrow.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org