numericalIntegrationScript.js

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/**
 * Class to handle numerical integration using Gauss quadrature
 */
export class numericalIntegration {
  /**
   * Constructor to initialize the numIntegration class
   * @param {string} meshDimension - The dimension of the mesh
   * @param {number} elementOrder - The order of elements
   */
  constructor({ meshDimension, elementOrder }) {
    this.meshDimension = meshDimension;
    this.elementOrder = elementOrder;
  }

  /**
   * Return Gauss points and weights based on element configuration
   * @returns {object} An object containing:
   *  - gaussPoints: Array of Gauss points
   *  - gaussWeights: Array of Gauss weights
   */
  getGaussPointsAndWeights() {
    let gaussPoints = []; // Gauss points
    let gaussWeights = []; // Gauss weights

    if (this.elementOrder === "linear") {
      // For linear elements, use 1-point Gauss quadrature
      gaussPoints[0] = 0.5;
      gaussWeights[0] = 1;
    } else if (this.elementOrder === "quadratic") {
      // For quadratic elements, use 3-point Gauss quadrature
      gaussPoints[0] = (1 - Math.sqrt(3 / 5)) / 2;
      gaussPoints[1] = 0.5;
      gaussPoints[2] = (1 + Math.sqrt(3 / 5)) / 2;
      gaussWeights[0] = 5 / 18;
      gaussWeights[1] = 8 / 18;
      gaussWeights[2] = 5 / 18;
    }

    return { gaussPoints, gaussWeights };
  }
}