TensorPart

Overview

txeo::TensorPart is a utility class that provides static methods to partition and manipulate tensors and matrices. It is especially useful for preprocessing operations like slicing, unstacking, or extracting submatrices.

Template Parameter

• T: Data type of tensor or matrix elements (e.g., int, float, double)

Methods

unstack(tensor, axis)

Unstacks a tensor along the specified axis.

#include "txeo/TensorPart.h"
#include "txeo/Tensor.h"
#include <iostream>

int main() {
    txeo::Tensor<int> tensor({{{1, 2, 3}, {4, 5, 6}}, {{7, 8, 9}, {10, 11, 12}}});

    auto unstacked_tensors = txeo::TensorPart<int>::unstack(tensor, 0);

    for (size_t i = 0; i < unstacked_tensors.size(); ++i) {
        std::cout << "Unstacked Tensor " << i << ":\n" << unstacked_tensors[i] << std::endl;
    }

    return 0;
}

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slice(tensor, first_axis_begin, first_axis_end)

Returns a slice of the tensor along its first axis (no copying).

#include <iostream>
#include "txeo/Tensor.h"
#include "txeo/TensorPart.h"

int main() {
    txeo::Tensor<int> tensor{{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
    auto sliced_tensor = txeo::TensorPart<int>::slice(tensor, 0, 2);

    std::cout << "Sliced Tensor: " << sliced_tensor << std::endl;
    return 0;
}

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increase_dimension(tensor, axis, value)

Returns a new tensor with an inserted dimension filled with a specific value.

txeo::Tensor<T> increase_dimension(const txeo::Tensor<T>& tensor, size_t axis, T value);

---

increase_dimension_by(tensor, axis, value)

Modifies the tensor in-place, inserting a new dimension.

txeo::Tensor<T>& increase_dimension_by(txeo::Tensor<T>& tensor, size_t axis, T value);

---

sub_matrix_cols(matrix, cols)

Returns a submatrix with only the selected columns.

txeo::Matrix<T> sub_matrix_cols(const txeo::Matrix<T>& matrix, const std::vector<size_t>& cols);

---

sub_matrix_cols_exclude(matrix, cols)

Returns a submatrix excluding specified columns.

txeo::Matrix<T> sub_matrix_cols_exclude(const txeo::Matrix<T>& matrix, const std::vector<size_t>& cols);

---

sub_matrix_rows(matrix, rows)

Returns a submatrix with the specified rows.

txeo::Matrix<T> sub_matrix_rows(const txeo::Matrix<T>& matrix, const std::vector<size_t>& rows);

---

Exceptions

TensorPartError

Thrown when a tensor or matrix operation fails.

class TensorPartError : public std::runtime_error;

---

Example: Unstacking

txeo::Tensor<int> t({{{1,2,3}, {4,5,6}}, {{7,8,9}, {10,11,12}}});
auto slices = txeo::TensorPart<int>::unstack(t, 0);

Example: Column Submatrix

txeo::Matrix<double> m(2, 3, {1.1, 2.2, 3.3, 4.4, 5.5, 6.6});
auto sub = txeo::TensorPart<double>::sub_matrix_cols(m, {0, 2});

For detailed API references, see individual method documentation at txeo::TensorPart.