heterogen_table.cpp

/*******************************************************************************
* Copyright 2023 Intel Corporation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*     http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*******************************************************************************/

#include <memory>
#include <iostream>

#include "example_util/utils.hpp"

#include "oneapi/dal/table/common.hpp"
#include "oneapi/dal/chunked_array.hpp"
#include "oneapi/dal/table/heterogen.hpp"

#include "oneapi/dal/table/row_accessor.hpp"

namespace dal = oneapi::dal;

// Generate a sequence of numbers
// allocated on host
template <typename Type = float>
dal::array<Type> get_arange(std::int64_t count, std::int64_t first = 0l, std::int64_t step = 1l) {
    auto* const raw_data = new Type[count];

    for (std::int64_t i = 0l; i < count; ++i) {
        std::int64_t value = step * i + first;
        raw_data[i] = static_cast<Type>(value);
    }

    // Create an array using raw pointer and delete[ ]
    return dal::array<Type>(raw_data,
                            count, //
                            [](Type* const ptr) -> void {
                                delete[] ptr;
                            });
}

// Generate a chunked array on host
// with a specified number of chunks
template <typename Type = float>
dal::chunked_array<Type> get_chunked_arange(std::int64_t count, std::int64_t chunk_count = 2l) {
    dal::chunked_array<Type> chunked_array(chunk_count);

    std::int64_t min_count = count / chunk_count;
    for (std::int64_t i = 0l; i != chunk_count; ++i) {
        std::int64_t first = i * min_count;
        std::int64_t local_count = (i + 1 == chunk_count) ? (count - first) : min_count;
        auto chunk = get_arange<Type>(local_count, first);
        chunked_array.set_chunk(i, chunk);
    }

    return chunked_array;
}

int main(int argc, char** argv) {
    constexpr std::int64_t row_count = 24;

    // Generate data on the host with different types and
    // different numbers of chunks
    auto column_1 = get_chunked_arange<float>(row_count, 1);
    auto column_2 = get_chunked_arange<double>(row_count, 2);
    auto column_3 = get_chunked_arange<std::int8_t>(row_count, 3);
    auto column_4 = get_chunked_arange<std::int16_t>(row_count, 4);
    auto column_5 = get_chunked_arange<std::uint32_t>(row_count, 5);

    // Wrap different columns into a single non-typed
    // heterogeneous table
    dal::table test_table = dal::heterogen_table::wrap( //
        column_1,
        column_2,
        column_3,
        column_4,
        column_5);

    // Sanity checks for the table shape
    std::cout << "Number of rows in table: " << test_table.get_row_count() << '\n';
    std::cout << "Number of columns in table: " << test_table.get_column_count() << '\n';

    // Check the type of abstract table
    const bool is_heterogen = test_table.get_kind() == dal::heterogen_table::kind();
    std::cout << "Is heterogeneous table: " << is_heterogen << '\n';

    // Extract row slice of data on the host
    dal::row_accessor<const double> accessor{ test_table };
    dal::array<double> slice = accessor.pull({ 3l, 17l });

    std::cout << "Slice of elements: " << slice << std::endl;

    return 0;
}