ArrayBase

ArrayBase

Header: include/stratax/core/ArrayBase.hpp.

ArrayBase owns a Buffer of elements, a Shape, and a Shape of canonical row-major strides. Constructors and assignment helpers are protected. Vector, Matrix, and Tensor add rank constraints and multidimensional interfaces.

Invariants and access

size() == shape().elements() and rank() == shape().rank() == strides().rank(). Nonempty storage is contiguous. Public shape and stride references are read-only. Metadata queries size/empty/rank/shape/strides take O(1).

Flat operator[] is unchecked and requires an index below size. Signed at(i) normalizes negative indices and throws IndexError outside [-size, size). front/back also throw IndexError on empty arrays. data returns null for empty owning storage. Forward, const, and reverse iterators traverse the flat sequence; iterator acquisition is O(1), and full traversal and fill take O(n).

Construction and assignment

Shape constructors value-initialize elements or copy a fill value, copy the shape, and compute strides. They take O(n + r) time/storage and propagate DimensionError for count/stride overflow and allocation/element exceptions. The buffer-adopting constructor moves the buffer before verifying its count; on failure the adopted storage is released during unwinding.

Copy construction deeply copies all three buffers. Copy assignment uses copy-and-swap across the whole state, giving a strong exception guarantee. Copy assignment costs O(old size + new size + old rank + new rank). Base moves transfer all buffers and leave a distinct source empty with rank zero. Base move construction is O(1) and noexcept; move assignment also destroys old state. Derived Vector/Matrix moves restore fixed-rank empty source metadata and can allocate, so they are not noexcept.

swap exchanges all buffers in O(1). Pointers/iterators keep referring to the same allocation under its new owner. Calling base swap must preserve the receiving derived rank invariants; do not exchange a Vector base with a Matrix base. Assignment can release destination storage and invalidate its references.

Checked multidimensional helper

normalized_flat_offset accepts a sized, indexable sequence of signed indices without caller-supplied messages. It first checks rank with RankError, then rejects empty storage with IndexError (including rank zero and an empty index sequence), then checks each component with normalize_index/IndexError. It combines indices and strides in O(r). Public multidimensional interfaces belong to the derived containers.

#include <stratax.h>
#include <cassert>
 
int main() {
    stratax::container::Matrix<double> source{{1.0, 2.0}, {3.0, 4.0}};
    auto copy = source;
    copy.fill(9.0);
    assert(source.at(-1) == 4.0);
    assert(copy.size() == copy.shape().elements());
    assert(copy.rank() == copy.strides().rank());
}

See Buffer, Vector, Matrix, and Tensor. Exact member signatures are available in the generated ArrayBase reference.