Implementation of correlate (#2180)

* Implementation of dot product sliding window which is can be used to
implement both `correlate` and `convolve` functions.
* Implementation of `correlate` function using dot product sliding
window

Author: AlexanderKalistratov

dpnp/backend/extensions/statistics/CMakeLists.txt

@@ -26,12 +26,15 @@
 
 set(python_module_name _statistics_impl)
 set(_module_src
-    ${CMAKE_CURRENT_SOURCE_DIR}/common.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/bincount.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/common.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/histogram.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/histogramdd.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/histogram_common.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/sliding_dot_product1d.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/sliding_window1d.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/statistics_py.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/validation_utils.cpp
 )
 
 pybind11_add_module(${python_module_name} MODULE ${_module_src})

dpnp/backend/extensions/statistics/bincount.hpp

@@ -33,9 +33,7 @@
 
 namespace dpctl_td_ns = dpctl::tensor::type_dispatch;
 
-namespace statistics
-{
-namespace histogram
+namespace statistics::histogram
 {
 struct Bincount
 {
@@ -63,5 +61,4 @@ struct Bincount
 };
 
 void populate_bincount(py::module_ m);
-} // namespace histogram
-} // namespace statistics
+} // namespace statistics::histogram

dpnp/backend/extensions/statistics/common.cpp

@@ -29,11 +29,8 @@
 
 namespace dpctl_td_ns = dpctl::tensor::type_dispatch;
 
-namespace statistics
+namespace statistics::common
 {
-namespace common
-{
-
 size_t get_max_local_size(const sycl::device &device)
 {
     constexpr const int default_max_cpu_local_size = 256;
@@ -120,5 +117,4 @@ pybind11::dtype dtype_from_typenum(int dst_typenum)
     }
 }
 
-} // namespace common
-} // namespace statistics
+} // namespace statistics::common

dpnp/backend/extensions/statistics/common.hpp

@@ -35,9 +35,7 @@
 
 namespace type_utils = dpctl::tensor::type_utils;
 
-namespace statistics
-{
-namespace common
+namespace statistics::common
 {
 
 template <typename N, typename D>
@@ -187,5 +185,4 @@ sycl::nd_range<1>
 // headers of dpctl.
 pybind11::dtype dtype_from_typenum(int dst_typenum);
 
-} // namespace common
-} // namespace statistics
+} // namespace statistics::common

dpnp/backend/extensions/statistics/dispatch_table.hpp

@@ -39,11 +39,8 @@
 namespace dpctl_td_ns = dpctl::tensor::type_dispatch;
 namespace py = pybind11;
 
-namespace statistics
+namespace statistics::common
 {
-namespace common
-{
-
 template <typename T, typename Rest>
 struct one_of
 {
@@ -97,6 +94,32 @@ using DTypePair = std::pair<DType, DType>;
 using SupportedDTypeList = std::vector<DType>;
 using SupportedDTypeList2 = std::vector<DTypePair>;
 
+template <typename FnT,
+          typename SupportedTypes,
+          template <typename>
+          typename Func>
+struct TableBuilder
+{
+    template <typename _FnT, typename T>
+    struct impl
+    {
+        static constexpr bool is_defined = one_of_v<T, SupportedTypes>;
+
+        _FnT get()
+        {
+            if constexpr (is_defined) {
+                return Func<T>::impl;
+            }
+            else {
+                return nullptr;
+            }
+        }
+    };
+
+    using type =
+        dpctl_td_ns::DispatchVectorBuilder<FnT, impl, dpctl_td_ns::num_types>;
+};
+
 template <typename FnT,
           typename SupportedTypes,
           template <typename, typename>
@@ -124,6 +147,78 @@ struct TableBuilder2
         dpctl_td_ns::DispatchTableBuilder<FnT, impl, dpctl_td_ns::num_types>;
 };
 
+template <typename FnT>
+class DispatchTable
+{
+public:
+    DispatchTable(std::string name) : name(name) {}
+
+    template <typename SupportedTypes, template <typename> typename Func>
+    void populate_dispatch_table()
+    {
+        using TBulder = typename TableBuilder<FnT, SupportedTypes, Func>::type;
+        TBulder builder;
+
+        builder.populate_dispatch_vector(table);
+        populate_supported_types();
+    }
+
+    FnT get_unsafe(int _typenum) const
+    {
+        auto array_types = dpctl_td_ns::usm_ndarray_types();
+        const int type_id = array_types.typenum_to_lookup_id(_typenum);
+
+        return table[type_id];
+    }
+
+    FnT get(int _typenum) const
+    {
+        auto fn = get_unsafe(_typenum);
+
+        if (fn == nullptr) {
+            auto array_types = dpctl_td_ns::usm_ndarray_types();
+            const int _type_id = array_types.typenum_to_lookup_id(_typenum);
+
+            py::dtype _dtype = dtype_from_typenum(_type_id);
+            auto _type_pos = std::find(supported_types.begin(),
+                                       supported_types.end(), _dtype);
+            if (_type_pos == supported_types.end()) {
+                py::str types = py::str(py::cast(supported_types));
+                py::str dtype = py::str(_dtype);
+
+                py::str err_msg =
+                    py::str("'" + name + "' has unsupported type '") + dtype +
+                    py::str("'."
+                            " Supported types are: ") +
+                    types;
+
+                throw py::value_error(static_cast<std::string>(err_msg));
+            }
+        }
+
+        return fn;
+    }
+
+    const SupportedDTypeList &get_all_supported_types() const
+    {
+        return supported_types;
+    }
+
+private:
+    void populate_supported_types()
+    {
+        for (int i = 0; i < dpctl_td_ns::num_types; ++i) {
+            if (table[i] != nullptr) {
+                supported_types.emplace_back(dtype_from_typenum(i));
+            }
+        }
+    }
+
+    std::string name;
+    SupportedDTypeList supported_types;
+    Table<FnT> table;
+};
+
 template <typename FnT>
 class DispatchTable2
 {
@@ -288,5 +383,4 @@ class DispatchTable2
     Table2<FnT> table;
 };
 
-} // namespace common
-} // namespace statistics
+} // namespace statistics::common

dpnp/backend/extensions/statistics/histogram.cpp

@@ -26,9 +26,7 @@
 #include <algorithm>
 #include <complex>
 #include <memory>
-#include <string>
-#include <type_traits>
-#include <unordered_map>
+#include <tuple>
 #include <vector>
 
 #include <pybind11/pybind11.h>

dpnp/backend/extensions/statistics/histogram.hpp

@@ -31,11 +31,7 @@
 #include "dispatch_table.hpp"
 #include "dpctl4pybind11.hpp"
 
-namespace dpctl_td_ns = dpctl::tensor::type_dispatch;
-
-namespace statistics
-{
-namespace histogram
+namespace statistics::histogram
 {
 struct Histogram
 {
@@ -61,5 +57,4 @@ struct Histogram
 };
 
 void populate_histogram(py::module_ m);
-} // namespace histogram
-} // namespace statistics
+} // namespace statistics::histogram