CSC153.01, 2004S Class 7: Numeric Recursion Admin * Read "Local Bindings in Scheme" * Does anyone look at these Eboards? * Questions on homework 2? * Convo: Argument: Technology keeps speeding things up, making our lives more busy and complicated. It's difficult to have "alone time"/"contemplative time". And that's a problem we need to solve. * Mental health and counseling * Sam's stupid weekend plan: Go to Minnesota, Go to ice carnival *at night* Overview: * Quick overview * Observation: Recursive type definitions lead to recursive procedures * Lab Quick info on numeric recursion: * Recursion can occur over "any" type that you can simplfy * For whole numbers, you can stop at 0 or 1 and simplify by subtracting 1 * For whole numbers, you can stop at 1 and simplify by dividing by 2 Lists and Whole numbers are nice for recursion, because they are typically defined recursively A list is either: * Null (base base) * cons of anything and "a list" A whole number is either * 0 * Successor of another whole number Any questions? Do the lab At 10:40, we will discuss techniques of exponentiation. See Examples/expt.scm