hashing.hpp
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16 #pragma once
17 
18 #include <cudf/table/table.hpp>
20 
21 namespace cudf {
22 
23 using hash_value_type = uint32_t;
24 
34 enum class hash_id {
35  HASH_IDENTITY = 0,
36  HASH_MURMUR3,
37  HASH_SERIAL_MURMUR3,
38  HASH_SPARK_MURMUR3,
39  HASH_MD5
40 };
41 
45 static constexpr uint32_t DEFAULT_HASH_SEED = 0;
46 
57 std::unique_ptr<column> hash(
58  table_view const& input,
59  hash_id hash_function = hash_id::HASH_MURMUR3,
60  uint32_t seed = DEFAULT_HASH_SEED,
61  rmm::mr::device_memory_resource* mr = rmm::mr::get_current_device_resource());
62  // end of group
64 } // namespace cudf
table_view.hpp
Class definitions for (mutable)_table_view
cudf::table_view
A set of cudf::column_view's of the same size.
Definition: table_view.hpp:154
cudf::hash
std::unique_ptr< column > hash(table_view const &input, hash_id hash_function=hash_id::HASH_MURMUR3, uint32_t seed=DEFAULT_HASH_SEED, rmm::mr::device_memory_resource *mr=rmm::mr::get_current_device_resource())
Computes the hash value of each row in the input set of columns.
cudf::hash_id
hash_id
Identifies the hash function to be used.
Definition: hashing.hpp:34
cudf
cuDF interfaces
Definition: aggregation.hpp:34
cudf::hash_id::HASH_IDENTITY
@ HASH_IDENTITY
Identity hash function that simply returns the key to be hashed.
table.hpp
Class definition for cudf::table.
rmm::mr::device_memory_resource