reduction.hpp
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1 /*
2  * SPDX-FileCopyrightText: Copyright (c) 2019-2026, NVIDIA CORPORATION.
3  * SPDX-License-Identifier: Apache-2.0
4  */
5 
6 #pragma once
7 
8 #include <cudf/aggregation.hpp>
9 #include <cudf/scalar/scalar.hpp>
10 #include <cudf/utilities/export.hpp>
12 
13 #include <optional>
14 
15 namespace CUDF_EXPORT cudf {
25 enum class scan_type : bool { INCLUSIVE, EXCLUSIVE };
26 
27 // clang-format off
91 std::unique_ptr<scalar> reduce(
92  column_view const& col,
93  reduce_aggregation const& agg,
94  data_type output_type,
97 // clang-format on
98 
120 std::unique_ptr<scalar> reduce(
121  column_view const& col,
122  reduce_aggregation const& agg,
123  data_type output_type,
124  std::optional<std::reference_wrapper<scalar const>> init,
127 
171 std::unique_ptr<column> segmented_reduce(
172  column_view const& segmented_values,
174  segmented_reduce_aggregation const& agg,
175  data_type output_type,
176  null_policy null_handling,
179 
197 std::unique_ptr<column> segmented_reduce(
198  column_view const& segmented_values,
200  segmented_reduce_aggregation const& agg,
201  data_type output_type,
202  null_policy null_handling,
203  std::optional<std::reference_wrapper<scalar const>> init,
206 
225 std::unique_ptr<column> scan(
226  column_view const& input,
227  scan_aggregation const& agg,
229  null_policy null_handling = null_policy::EXCLUDE,
232 
243 std::pair<std::unique_ptr<scalar>, std::unique_ptr<scalar>> minmax(
244  column_view const& col,
247 
251 namespace reduction {
260 } // namespace reduction
261  // end of group
263 
264 } // namespace CUDF_EXPORT cudf
Representation for specifying desired aggregations from aggregation-based APIs, e....
Kind
Possible aggregation operations.
Definition: aggregation.hpp:79
A non-owning, immutable view of device data as a column of elements, some of which may be null as ind...
Indicator for the logical data type of an element in a column.
Definition: types.hpp:278
Derived class intended for reduction usage.
Derived class intended for scan usage.
Derived class intended for segmented reduction usage.
std::unique_ptr< column > segmented_reduce(column_view const &segmented_values, device_span< size_type const > offsets, segmented_reduce_aggregation const &agg, data_type output_type, null_policy null_handling, std::optional< std::reference_wrapper< scalar const >> init, rmm::cuda_stream_view stream=cudf::get_default_stream(), rmm::device_async_resource_ref mr=cudf::get_current_device_resource_ref())
Compute reduction of each segment in the input column with an initial value. Only SUM,...
scan_type
Enum to describe scan operation type.
Definition: reduction.hpp:25
std::unique_ptr< column > scan(column_view const &input, scan_aggregation const &agg, scan_type inclusive, null_policy null_handling=null_policy::EXCLUDE, rmm::cuda_stream_view stream=cudf::get_default_stream(), rmm::device_async_resource_ref mr=cudf::get_current_device_resource_ref())
Computes the scan of a column.
std::unique_ptr< scalar > reduce(column_view const &col, reduce_aggregation const &agg, data_type output_type, std::optional< std::reference_wrapper< scalar const >> init, rmm::cuda_stream_view stream=cudf::get_default_stream(), rmm::device_async_resource_ref mr=cudf::get_current_device_resource_ref())
Computes the reduction of the values in all rows of a column with an initial value.
std::pair< std::unique_ptr< scalar >, std::unique_ptr< scalar > > minmax(column_view const &col, rmm::cuda_stream_view stream=cudf::get_default_stream(), rmm::device_async_resource_ref mr=cudf::get_current_device_resource_ref())
Determines the minimum and maximum values of a column.
rmm::cuda_stream_view const get_default_stream()
Get the current default stream.
inclusive
Enum used to define whether or not bins include their boundary points.
Definition: label_bins.hpp:25
rmm::device_async_resource_ref get_current_device_resource_ref()
Get the current device memory resource reference.
cuda::mr::resource_ref< cuda::mr::device_accessible > device_async_resource_ref
cuda::std::span< T, Extent > device_span
Device span is an alias of cuda::std::span.
Definition: span.hpp:320
null_policy
Enum to specify whether to include nulls or exclude nulls.
Definition: types.hpp:116
bool is_valid_aggregation(data_type source, aggregation::Kind kind)
Indicate if a reduction is supported for a source datatype.
cuDF interfaces
Definition: host_udf.hpp:26
Class definitions for cudf::scalar.