Numerical Computation

Posted on September 1, 2024

ch 1: numerical algorithms

  • mathematical model: formulated as an attempt to explain/understand
  • continuous/piecewise problem approximated by discrete one
  • functions approximated by finite arrays
  • algorithms solve mathematical problems
  • numerical analysis is the theory behind such algorithms

1.2 error

  • absolute error: |u − v|
  • relative error: |u − v|/|u|

error types

  1. errors in the problem to be solved:
    • approximation errors in the mathematical model
    • errors in input data
  2. approximation errors
    • discretization errors: diecretization of continuos process
    • convergence errors: arise in iterative methods, since nonlinear problems can be solved by infinitely many iterations
  3. roundoff errors
    • due to finite precision representation of real numbers on computers

Big-O Notation