31 May
2002
31 May
'02
4:37 p.m.
Alastair Reid (reid@cs.utah.edu) wrote:
Are you reporting a bug in Hugs or asking us to debug your code?
Sorry, I should have been more clear. I think it's a bug. Main> :version -- Hugs Version February 2001 Main> asin (-2 / 2.0) -1.5708 Main> norm (b, a) * norm (b, c) 2.0 Main> asin (-2 / (norm (b, a) * norm (b, c))) nan.0 where a = (1,0); b = (0,1); c = (1,2) norm ((x1, y1), (x2, y2)) = sqrt ((x1 - x2)^2 + (y1 - y2)^2) It /looks/ like a bug to me, but there may be some mysterious deep number magic I missed which explains this behaviour. -Adrian