Data Fields

Methods

{
  "name": "SumEngine",
  "namespace": "sofa::component::engine::analyze",
  "module": "Sofa.Component.Engine.Analyze",
  "include": "sofa/component/engine/analyze/SumEngine.h",
  "doc": "Computing the sum between two vector of dofs.\n\nComputing the Sum between two vector of dofs\noutput = input - substractor",
  "inherits": [
    "DataEngine"
  ],
  "templates": [
    "Vec1",
    "Vec3"
  ],
  "data_fields": [
    {
      "name": "d_input",
      "type": "VecData",
      "xmlname": "input",
      "help": "input vector"
    },
    {
      "name": "d_output",
      "type": "DataType",
      "xmlname": "output",
      "help": "output sum"
    }
  ],
  "links": [],
  "methods": [
    {
      "name": "init",
      "return_type": "void",
      "params": [],
      "is_virtual": true,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "public"
    },
    {
      "name": "reinit",
      "return_type": "void",
      "params": [],
      "is_virtual": true,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "public"
    },
    {
      "name": "doUpdate",
      "return_type": "void",
      "params": [],
      "is_virtual": true,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "public"
    }
  ],
  "description": "The **SumEngine** is a component within the SOFA framework designed to compute the sum between two vectors of degrees-of-freedom (DOFs). It operates by taking an input vector and computing its sum, outputting the result as another DOF vector.\n\n### Role in SOFA Ecosystem:\n- The **SumEngine** inherits from `DataEngine`, a core engine component within SOFA. This implies it processes data related to mechanical states or other simulation aspects, contributing to the overall analysis pipeline.\n- It operates on generic types (e.g., `Vec1` and `Vec3`) to provide flexibility in handling different dimensions of input vectors.\n\n### Interactions with Other Components:\n- **DataEngine Inheritance**: As a derived class from `DataEngine`, it integrates into the SOFA scene graph architecture, enabling interaction with other engines and components through the standard initialization (`init`), reinitialization (`reinit`), and update (`doUpdate`) methods.\n\n### Practical Usage Guidance:\n- **Input Field** (`input`): This field expects a vector of degrees-of-freedom. The input can be from another SOFA component or directly specified in the XML scene description file.\n- **Output Field** (`output sum`): The output of the engine is the computed sum of the input vector elements, stored as a single degree-of-freedom value (either `Vec1` or `Vec3`).\n\n### Data Fields:\n- **d_input**: Represents the input vector for which the sum needs to be calculated.\n- **d_output**: Holds the result after computing the sum of the elements in the input vector.",
  "maths": "The **SumEngine** is a component within the SOFA framework designed to compute the sum of elements in an input vector. This operation can be mathematically described as follows:\n\nGiven an input vector \\(\\mathbf{v} = [v_1, v_2, \\\\ldots, v_n]\\), where each \\(v_i\\) is a degree-of-freedom (DOF), the **SumEngine** computes the sum of its elements. The output \\(s\\) is given by:\n\n\begin{equation}\n    s = \\sum_{i=1}^n v_i\n\tag{1}\n\nd_output = s.\n\tag{2}\n\nd_input = [v_1, v_2, \\\\ldots, v_n].\n\tag{3}\n\\end{equation}\n\n### Role in the Global FEM Pipeline:\n- **Data Processing**: The **SumEngine** acts as a data processing component within the SOFA framework. It is not directly involved in the core FEM operations such as mass matrix \\(M\\), stiffness matrix \\(K\\), or internal force \\(f_{int}\\) computation, but rather provides utility for analyzing the state of DOFs.\n- **Initialization and Update**: The component initializes its input and output data fields. During each update step (via `doUpdate` method), it computes the sum of elements in the input vector and stores the result in the output field.\n\n### Numerical Methods or Discretization Choices:\n- The operation performed by the **SumEngine** is a straightforward summation using the standard library function `std::accumulate`. No specific numerical methods or discretizations are involved, as this component focuses on simple data aggregation rather than FEM-specific operations.\n\n### Integration with Variational / Lagrangian Mechanics Framework:\n- The **SumEngine** does not directly contribute to variational formulations or the Euler-Lagrange equations. It serves more as a utility for post-processing or analysis within the SOFA framework, providing flexibility in handling different types of input vectors (e.g., \\(Vec1\\) and \\(Vec3\\)).\n\n### Constitutive Laws and Kinematic Laws:\n- The **SumEngine** does not involve any constitutive or kinematic laws. It is purely a computational tool for summing elements in a vector, which may be used in various contexts within the simulation pipeline.",
  "abstract": "The SumEngine computes the sum of elements in an input vector, outputting the result as a single degree-of-freedom value.",
  "sheet": "# SumEngine\n\n## Overview\nSumEngine inherits from `DataEngine` and computes the sum of elements in an input vector. It processes data related to mechanical states or other simulation aspects.\n\n## Mathematical Model\nGiven an input vector \\(\\mathbf{v} = [v_1, v_2, \\ldots, v_n]\\), where each \\(v_i\\) is a degree-of-freedom (DOF), the SumEngine computes the sum of its elements. The output \\(s\\) is given by:\n\n\\[ s = \\sum_{i=1}^n v_i \\]\n\nThe result is stored in the `d_output` field.\n\n## Parameters and Data\n- **d_input**: Represents the input vector for which the sum needs to be calculated. Type: VecData.\n- **d_output**: Holds the computed sum of the elements in the input vector. Type: DataType."
}