FYI: In J7.01 the monad ^...@j. is supported by special code, so that: ^...@o. 0 j. 0.5 * i. 3 4 1 0j1 _1 0j_1 1 0j1 _1 0j_1 1 0j1 _1 0j_1
^...@o. 0 j. 2e9 + 0.5 * i. 3 4 1 0j1 _1 0j_1 1 0j1 _1 0j_1 1 0j1 _1 0j_1 ----- Original Message ----- From: DIETER ENSSLEN <[email protected]> Date: Tuesday, January 19, 2010 13:51 Subject: [Jchat] J and CAS, and problems in CAS To: chat forum <[email protected]> > CAS computer algebra systems > > e^(pi *i)+ 1 actually equals a nice zero, yes it is nice > OK OK OK > > I do look forward to more of CAS in J. > > But there lurk problems in that world, too: > The world's most powerful and best graphing calculator, the TI > Nspire cas evaluates the integral from -1 to 1 of 1/sqrt(1-x^2) > nicely as 'pi' in symbol form. > > then if you ask for the approximation of that 'pi' you get a > number that is different from the regular 'pi' by two > significant digits?! ..5862 vs ..5898 , the last figures > to 14 places. A difference of -3.6e-12. J gives ..5897 931. > > this must make sense to some or many of you. Good luck in the > move towards 'cas' > > by the way, this my computer does not let me type TI-Nspire > followed with the capital letters CAS without dropping the line > again and again and again. This too must make sense to several > of you. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
