On Tue, Oct 18, 2011 at 11:30 AM, David Vaughan <[email protected]> wrote: > Can J represent surds exactly instead of reverting to floating point? It > would be more convenient if I could do that rather than storing the squared > version.
Yes, but by generating a verb which would generate the floating point value and not as a number. cubeRootOf5=: %:&5 bind 3 Of course you can manipulate the resulting numbers but those results are still floating point: (cubeRootOf5 ^ 3:) '' 5 5-(cubeRootOf5 ^ 3:) '' 8.88178e_16 That said, in some cases, J can clean up floating point discrepancies 5-x:(cubeRootOf5 ^ 3:) '' 0 but that's from direct manipulation of the values and does not care about delayed evaluation: 5-x:((3 %:5) ^ 3:) '' 0 Anyways, J implements the data structures to support symbolic manipulation but it does not have a particularly large library of prebuilt symbolic manipulation routines. FYI, -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
