A34 The command draw3dmatrix takes a matrix from the stack and plots it as a 3d-surface. The raw-column coordinates of the numbers in the matrix are assumed to be the x-y-coordinates. Take for example the matrix: [[3 5] [4 7]] the first number at position 1,1 will be plotted as the point with x=1, y=1. The number itself is the z-coordinate. So we have x=1,y=1,z=3. The number at position 1,2 of the matrix will have x=1,y=2,z=5. And so on. Of course the x-y coordinates can be also interpreted as being all multiplied by a constant. In this example we could also interpret for the first point x=.5,y=.5,z=3 , and for the second x=.5,y=1,z=5 . That means, scale of x-y doesn`t matter. The only thing that matters is that the data must be even spaced in x-y. How much space between two adjacent points in x or y-direction is not important as long as it remains the same between all adjacent points. I think the plot type 3d-conic is not available. The example you give could be plotted as z=+sqrt(x^2+ÿ^2-4) and then (without erasing the plot or changing the plot parameter) plotting z=-sqrt(x^2+ÿ^2-4). 1 Yes, I did not mean otherwise, as to serious bugs, but I don't think anyone got any significant free upgrades (e.g. S version to G version), nor could you upgrade to any level you want, at any time you want, without limit. For one very serious bug in 48GX(M), HP just kept on selling the 48G with that same ROM version (which had other more minor bugs too) -- the *major* bug of which I speak was the covered port STO bug, for which the STOFIX library was created as a patch. Now, HP did give early 48GX(M) purchasers a period of time during which they could exchange their bad units, if you used RAM cards and realized soon enough that it was bad, but HP also cleverly used up the supply of already-produced bad ROMs in the 48G(M) [non-expandable] model, where that big, bad bug had no impact -- because there could be no cards plugged in! This was in fact the very one which I bought in 1993, for my first HP48, so I'd better not expand its memory, or else I won't even be able to use the extra ports; in fact, this bug would even be present if I used that ROM in Emu48, but fortunately HP now permits the use of any ROM by anyone in an emulator, whether or not it came with your own calculator. But flash (plus the extra programming required) are also costs, and thorough testing is another way to reduce trade-in expenses. By the way, how easy are the 39G and 40G to repair? It couldn't have anything to do with the other influences upon sales, could it -- or from looking over their shoulder at TI's flash calcs? Sherlock Holmes, on the other hand, might point out that HP's internal calculator regression testing produces no published results, and has nothing to do with comparing products -- it is nothing other than an internal quality control procedure, which I'd expect to be a mandated corporate policy as well. No one can generate security holes as fast as Microsoft (which proves that they *are* a monopoly, after all ;) MS also has to respond to what would otherwise be worse publicity, were it all the hole-finders who published first; by being their own confessor, they get to put a positive spin on everything (Mitigating factors: If you don't install a Microsoft web server on your system, this vulnerability will not occur ;-) When I worked on one of the first national election reporting computer systems, my company's project manager kept expecting things to keep working the same way each time that they were run, but in fact, there were already too many factors involved to repeatedly get the exact same line-up of events (particularly when a few precincts reported 105% of their votes tallied, but that may have been in Mayor Daley's region :) I'd bet against any management within HP ever going along with that. The 49G official releases have probably done as well as in the history of the 48. There are very few bugs right now, even in the current beta, so isn't it just as good as 48G-R, which still has some bugs, though well known and few? I'd be surprised if any of the 49G developers are being assigned any current work at all on the 49G; the clock (and calendar) must by now have run out on official R&D investment, on a product that marketers can barely establish at all in the educational field. My vague impression is that the 49G became a stepping stone to the 39G and 40G, and is no longer significant (except to us), as far as it may be regarded by HP management. But I'd be happy to be wrong! again, depends: if I sum f(0)+f(1) and I get 0.6 instead of 0.9, this is serious. The 49 is a CALCULATOR, not a gameboy. (RS-STO) doesn't make much sense when nothing is selected. So I did the following key bind, based on the standard action of CUT (use SA from Keyman): :: PTR 19B41 ( Maybe unstable! ) CK0NOLASTWD ( -- added code ) RCL_CMD_DEB RCL_CMD_FIN #=case ( -- end of added code ) CMD_COPY CMD_CUT ; RCL_CMD_DEB RCL_CMD_FIN #= will return FALSE if something is selected, and TRUE else. I assigned this to both RS K (32.3) and Alpha RS K (32.6). Now the important part of this post: Could you add this to the AsnKeys option of Emacs? Another suggestion: LS-hold-Up can be used for scrolling up very fast, so I propose changing the SDiag standard assignment to LS-hold-Left (and Alpha LS-hold-Left of course). That's what I have, and I think it's easier to use. Playing with my code I realized it must be done a bit different: :: PTR 19B41 CK0NOLASTWD RCL_CMD_DEB RCL_CMD_FIN #