http://www.jsoftware.com/help/dictionary/d300.htm
On Fri, Jul 11, 2014 at 8:05 AM, Jon Hough <[email protected]> wrote: > Got it. Thank you. > > Although, I've never seen -/ .* before. Is it in the Dictionary somewhere? > > > Date: Fri, 11 Jul 2014 06:52:37 -0700 > > From: [email protected] > > To: [email protected] > > Subject: Re: [Jprogramming] Testing for singular matrices > > > > A matrix M is singular iff 0 = -/ .* M (determinant is 0). Matrix > algebra > > on a computer is a snakepit so sometimes you may have to a number with > tiny > > magnitude, instead of 0. One of the pleasures of rational numbers is the > > ability to use 0 here, no ifs or buts. > > > > > > > > On Fri, Jul 11, 2014 at 6:46 AM, Jon Hough <[email protected]> wrote: > > > > > Reading through the dictionary, I see that %. is only defined for > > > non-singular matrices. > > > http://www.jsoftware.com/help/dictionary/d131.htm > > > > > > If I accidentally use a singular matrix, I get a domain error. So my > > > question is, what is the best way to test for non-singularity in J?for > 2x2 > > > matrices, it is pretty simple. But for 8x8 matrices (for example) is > there > > > a standard verb used to test for singularity? > > > > > > > > > > > > > > > ---------------------------------------------------------------------- > > > For information about J forums see http://www.jsoftware.com/forums.htm > > > > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
