API Reference: Legolas::Array

Header: #include "Legolas/Array/Array.hxx"

The Legolas::Array class template represents an \(N\)-dimensional tensor with optional compile-time data interleaving along a designated dimension.

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Template Definition

namespace Legolas {

template <
    class SCALAR_TYPE, 
    int LEVEL, 
    int PACK_SIZE = 1, 
    int PACK_LEVEL = 1
>
class Array;

}

Template Parameters

• SCALAR_TYPE: The underlying arithmetic type (e.g. float, double, int).
• LEVEL: The dimensionality/rank of the array (\(1\) for 1D vectors, \(2\) for 2D matrices, etc.).
• PACK_SIZE: Number of problem instances interleaved contiguously in memory (\(P=1\) for scalar, \(P=4\) for NEON/SSE, \(P=8\) for AVX2, \(P=16\) for AVX-512). Default is 1.
• PACK_LEVEL: The dimension index along which interleaving occurs (\(1\)-based index, e.g. 2 for outer dimension of a 2D array). Default is 1.

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Constructors

// 1. Construct 1D vector of length size
Array<float, 1>(int size);

// 2. Construct 2D array of shape (s2, s1)
Array<float, 2, 4, 2>(int s2, int s1);

// 3. Construct with explicit Shape
Array(const Shape& shape);

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Member Functions

Element Access

// Returns element or sub-array at index i (inlined with LEGOLAS_ALWAYS_INLINE)
Element operator[](int i);
const Element operator[](int i) const;

Shape & Size

// Returns the shape of the array
const Shape& shape() const;

// Returns the number of elements in the current dimension
int size() const;

// Returns total number of scalar elements in the entire buffer
size_t flatSize() const;

Memory Initialization & Assignment

// Sets all elements to the specified scalar value
void fill(RealType value);

// Deep copy assignment
Array& operator=(const Array& other);

// Element-wise compound assignments
Array& operator+=(const Array& other);
Array& operator-=(const Array& other);
Array& operator*=(RealType scalar);

SIMD Vector Views

// Returns a packed view where elements are mapped to Legolas::NativeSimd<SCALAR_TYPE, PACK_SIZE>
PackedArrayView getPackedView();
const PackedArrayView getPackedView() const;

// Returns a flattened 1D view of packed vector registers
Array<PackedRealType, 1> getFlatPackedView();