IFEM: Intro to Matrix-based FEM

• Normal computations run element-by-element

  • Only consider one element at a time

• Matrix-based computations are holistic

  • One big matrix represents the whole system
  • Solve the matrix == solve the problem

• Row of matrix solves for “Degree of Freedom”

  • E.g., a node’s X coordinate
  • Typically a row has only a few nonzero entries
  • Around 106 degrees of freedom--106 rows