Class1.md

Class 1: Number Bases

Topics

• Number bases: decimal, binary, hexadecimal
• Signed number representations: signed magnitude, ones' complement, two's complement

Resources

• Review Make School's slides on number bases
• Read BetterExplained's article on number systems and bases
• Read Vaidehi Joshi's articles on binary and hexadecimal with beautiful drawings and excellent examples
• Play with Dan Wolff's live-updating base conversion calculator
• Review Wikipedia's comparison table of signed number representations
• Print and make a Flippy Do binary converter following Code.org's instructions
• Watch Harvard's hexadecimal video
• Watch Corey Schafer's understanding bases video
• Watch Tech Quickie's numbers and base systems video

Challenges

• Practice binary and hexadecimal conversions on number bases worksheet
• Implement base conversion functions for unsigned numbers using starter code:
  • Implement decode - decode digits in any base to a number
  • Implement encode - encode a number to digits in any base
  • Implement convert - convert digits in any base to digits in any base
  • Run python bases.py number base1 base2 to test convert on number
    • Example: python bases.py 42 10 2 should give the result 101010
  • Run pytest bases_test.py to run the unit tests and fix any failures
• Write additional unit tests to ensure your conversion algorithms are robust

Stretch Challenges

• Implement base conversion for fractional numbers using a radix point (try playing with the base conversion calculator to see how this works)
• Implement base conversion for negative binary numbers (using two's complement)