Components Decomposer

Overview

The Components decomposer breaks down vectors, matrices, and tensors into their individual scalar components. It uses physics-aware naming conventions for stress/strain tensors and numeric indexing for generic matrices.

Include

#include <dataframe/attributes/Components.h>

Class Definition

Components API

namespace df::attributes {

class Components : public GenDecomposer<Components> {
public:
    Strings names(
        const Dataframe& dataframe,
        DecompDimension targetDim,
        const SerieBase& serie,
        const String& name) const override;

    Serie<double> serie(
        const Dataframe& dataframe,
        DecompDimension targetDim,
        const std::string& name) const override;
};

}

Naming Conventions

The naming pattern depends on the data type and the decomposition dimension.

Scalar Decomposition

Type	Generated Names
`Vector2D`	`{name}x`, `{name}y`
`Vector3D`	`{name}x`, `{name}y`, `{name}z`
`Vector4D`	`{name}x`, `{name}y`, `{name}z`, `{name}w`
`Stress2D` / `Strain2D`	`{name}xx`, `{name}xy`, `{name}yy`
`Stress3D` / `Strain3D`	`{name}xx`, `{name}xy`, `{name}xz`, `{name}yy`, `{name}yz`, `{name}zz`
`Matrix2D`	`{name}11`, `{name}12`, `{name}21`, `{name}22`
`Matrix3D`	`{name}11`, `{name}12`, ..., `{name}33`
`Matrix4D`	`{name}11`, `{name}12`, ..., `{name}44`

Vector Decomposition

Groups components into vectors: {name}_1, {name}_2, etc.

Matrix Decomposition

Groups components into matrix rows: {name}_11, {name}_12, etc.

Supported Types

Category	Types
Vectors	`Vector2D`, `Vector3D`, `Vector4D`
Full Matrices	`Matrix2D`, `Matrix3D`, `Matrix4D`
Symmetric Matrices	`SMatrix2D`, `SMatrix3D`, `SMatrix4D`
Physics Tensors	`Stress2D`, `Stress3D`, `Strain2D`, `Strain3D`

Examples

Decomposing Vectors

using namespace df;

Serie<Vector3D> displacements = {{1,2,3}, {4,5,6}, {7,8,9}};

Dataframe df;
df.add("U", displacements);

attributes::Manager mgr(df);
mgr.addDecomposer(attributes::Components());

// Get scalar names: "Ux", "Uy", "Uz"
auto names = mgr.getNames(attributes::DecompDimension::Scalar);

// Extract individual components
auto ux = mgr.getSerie<double>("Ux");  // {1, 4, 7}
auto uy = mgr.getSerie<double>("Uy");  // {2, 5, 8}
auto uz = mgr.getSerie<double>("Uz");  // {3, 6, 9}

Decomposing Stress Tensors

using namespace df;

// Symmetric 3D stress tensor (6 unique components: xx, xy, xz, yy, yz, zz)
Serie<Stress3D> stresses = {
    {100, 20, 10, 80, 15, 60},   // node 0
    {110, 25, 12, 85, 18, 65}    // node 1
};

Dataframe df;
df.add("S", stresses);

attributes::Manager mgr(df);
mgr.addDecomposer(attributes::Components());

// Get all scalar names
auto names = mgr.getNames(attributes::DecompDimension::Scalar);
// -> "Sxx", "Sxy", "Sxz", "Syy", "Syz", "Szz"

// Extract shear stress component
auto sxy = mgr.getSerie<double>("Sxy");  // {20, 25}

Decomposing Generic Matrices

using namespace df;

Serie<Matrix3D> transforms = {
    {1,0,0, 0,1,0, 0,0,1},   // identity
    {2,0,0, 0,2,0, 0,0,2}    // scale by 2
};

Dataframe df;
df.add("M", transforms);

attributes::Manager mgr(df);
mgr.addDecomposer(attributes::Components());

// Scalar names: "M11", "M12", "M13", "M21", ..., "M33"
auto m11 = mgr.getSerie<double>("M11");  // {1, 2}
auto m12 = mgr.getSerie<double>("M12");  // {0, 0}