From Wikistix

Ok, so, it cost AUD $7, but it looks like you get what you pay for.

Bug 1

Tripped over this when calculating the bond angle in methane, the tetrahedral angle. First, in calculator-like format, with the calculators response at the end:

• Deg:2tan^-1√2 = 109.4712206
• Deg:90 + sin^-1(3^-1) = 109.4712206
• Deg:90 + sin^-1(3^-1) - 2tan^-1√2 = 2e-09
• Deg:sin^-1(3^-1) + 90 - 2tan^-1√2 = 2e-09
• Deg:2tan^-1√2 - 90 - sin^-1(3^-1) = 19.13138372 huh?

Those last three lines should be approximately zero, since but no matter how many parenthesis I put in, that last line refuses to work. Interestingly, switching to radians makes it work:

• Rad:2tan^-1√2 - Π÷2 - sin^-1(3^-1) = -2.4e-11

Bug 2

The random number generator is fine when running interactively, but when run in a tight loop, values tend toward 0 or 1.

Scl:-1000→A:Lbl 0:Ran# dt :Isz A:Goto 0

Let's have a look at some of the statistics variables:

• n = 1000
• 
• 
• 
• xσ_{n − 1} = 0

Ok, that's unexpected.