Algorithms

Return to List of Lectures

Previous Lecture

• Misc
  • Make grading appointments for lab 1
• Questions?
• Algorithms
  • Video lecture
    • Definition: sequence of steps for solving problem
    • Problem characterized by input that describes specific problem instance and output that describes solution
    • Steps are clear and effective
      • Effective: can be explained in whatever detail someone or something needs in order to really do it
        • “Find x such that x² - 2x + 1 = 0” doesn’t look effective at first
        • But can give more detail:
          • Compute x as (-b ± √(....))/2a
    • Algorithm must eventually stop
  • What do algorithms have to do with the expressions lab?
    • You’re writing algorithms in the lab (in Matlab)
    • Think about algorithm in pseudocode as an intermediate between vague ideas about problem and detailed Matlab
  • What do algorithms have to do with textbook section 3.5?
    • Can build next step from previous one(s)
    • In particular, often want to repeat previous step(s)
• Arithmetic Lab
• Next
  • User-defined functions
  • Read section 4.3 in textbook

Next Lecture