Class 40: Vectors, revisited

Held Wednesday, November 8, 2000

Summary

Today we consider the wonder of vectors in Scheme. Vectors are like lists, but with some limitations and benefits.

Notes

• Today's stuff:
  • Reading: Vectors
  • Lab: Vectors
• I hope you folks have recovered from staying up late last night. I gave my 9am class sympathy, but I'd like you folks to try to work.
• I notice that for many of you, attendance is becoming much more sporadic. I expect you to show up to class!
• I'll remind you about the deal I made (only applicable for those who attend).

Overview

• One list usage: Storing information on a thing (e.g,. a course).
• Observations:
  • Want to easily access any element (and quickly)
  • May want to change elements (and quickly)
  • Typically fixed size
• Result: Vector, a new data type
  • Costs the same amount to access each element. (vector-ref)
  • Allows you to change elements. (vector-set!)
  • Typically fixed size.
• Common methods:
  • vector
  • make-vector
  • vector?
  • vector-length
  • vector-ref
  • vector-set!
  • vector->list
  • vector-fill!
• Lab