What's New -  June, 2010

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June 5, 2010:  Last month's posting prompted viewer Erich to play with our Logic Problem Solver and expose a bug which has existed for years.  Did you know that given propositions "A implies B", "B implies C", and "A and C cannot both be true", then one can conclude that A is false?  My logical brain knew that back in 2002, but my programming finger slipped and I was declaring A to be true.  Logic Problem Solver Version 3.2 fixes it. 

June 15, 2010:  

Saw 1" boards leaving 12" Cant from 24" Log

Have you seen a modern sawmill with a computer controlled saw on TV?  The computer analyzes and displays for the operator's approval, the optimal sawing pattern for converting each log into boards based on laser measurements taken.  Smaller sawmill operators without computers or lasers to control their mills must perform the same task using their experience or some other strategy.  I'm not privileged to own a sawmill, but as a woodlot owner with a  woodworking hobby,  a small band mill is sure tempting.  Here is a program, Log Sawing Patterns, which I imagine could be developed into something useful if I ever succumb to the temptation. 
          

June 18, 2010:  The June 12th Mensa Puzzle-A-Day calendar puzzle asked for the two 2-digit numbers which are 3 times the product of their digits.  It took less than 20 lines of code to find the answers to this and for other multiples for all 2 and 3 digit numbers.  DigitProducts on the Beginner's page of our Delphi Techniques section has the source and executable to provide the answers.      

June 25, 2010: 

7 - a winner!

Craps is a dice game with scoring based sum of rolling 2 dice.   Craps Odds calculates the theoretical chances of winning or losing for each of the eleven possible initial roll outcomes (2 through 12). It also has a page which simulates a million games to verify that the theoretical probability results are valid.