B59 Yes. I cut a piece of clear plastic, & beveled the edges so it sits into the recess for the screen, but rests on the angled recess in the metal. It doesn't touch the LCD screen. I gingerly cut two very thin strips of double sided tape, applied them to the top & bottom beveled surfaces of my plastic screen protector, and used them to stick the plastic in place. The clear plastic I used isn't perfect, in that it dims the display a bit, and the display's contrast isn't that great anyway. I'm probably going to change to a strong tape hinge at the top of the screen, and a tiny double-sided tape dot at the bottom, so I can flip the plastic out of the way if the light isn't so good. ---------------------------------------------------------------------- A couple years ago I cut the back of a jewel case from a CD to 3 inches by 4.5 inches with a hacksaw. I taped the alpha key layout (including Greek letters), photocopied from the HP48 Handbook, to the plastic and placed it in the top of the pocket in the HP48 soft case. I haven't had any dents in the metal or broken keys since, and my screen has never broken, so it works well. Plus, I never have to look up an alpha key combination! I think the ideal case for a calculator is a soft case (like the HP48's) with hard reinforcements (like my plastic). This way there are no scratches (like a hard case gets) while still having protection for the keyboard and the LCD. Ideally I'd try to find a larger piece of plastic to protect the entire front of the calculator, but this was all I had on hand at the time, and it seems to work well enough. Eric Rechlin Bismarck, ND eric@ hpcalc.org http://www.hpcalc.org/ ----------- I've taken a piece of Masonite (the funny pressboard stuff that pegboard is made of) and cut it to size and slipped it into the pocket inside the HP's case. This protects not only the LCD but the keys as well. Stiff plastic should work just as well. Now I wonder if anyone has any ideas for cleaning a sticky key? I think I got soda or something on it. The Grapevine (publ.) HP48G/GX Pocket guide fits inside the standard original case, and affords some protection as well (if placed in front of the screen side); its front cover shows the complete alpha keyboard, with all alpha shift symbols. Donnelly's HP48 Pocket Book, on the other hand, is wider than the above, and would be even more protective -- if only it fit inside the case, which it doesn't quite do (so I put mine on the outside, held by unattractive rubber bands); Donnelly's front cover is just a photo of the calc. Since this question is about protecting the calc, rather than the content of the books, here are just the ISBN's of these fine companion publications: 0-931011-45-0 HP48G/GX Pocket Guide (Grapevine) 1-879828-05-7 HP48 Pocket Book (Donnelly, G-series) Perhaps you can, after all, tell a book by its cover :) ----------------------------------------------------------- ------------------ I wonder if there's a correlation between how often you've called them and how often their number has been changed? Steve ---------------------------------------------------------------------- I read a while back about a bad batch of hp48's where the screen went bad in the upper left hand corner. Mine had started already nback then but hasn't really gotten much worse. Anyways I broke the serial port so now it has to go in for service. So the question is Does anyone know if this was true(LCD failure) and if so who should I contact? And if I still can? I know I should have done it before but I couldn't imagine trying to do a double major in Physics and Aerospace Engineering without my trusty HP. Even if only for a few weeks ---------------------------------------------------------------------- The thing to do is to cheat: Let me recommend using one of the BMP files for Emu48 as your diagram - check out http://www.gulftel.com/~pattersc/emu48/ The one for 1024x768 seemed pretty good. Pete M. Wilson Gamewood Data Systems Internet Service wilsonpm@gamewood.net ---------------------------------------------------------------------- thats what i needed much thanks shayne. ---------------------------------------------------------------------- Anyone know where to find a good options program to help calculate binonmial pricing and black scholes, etc. The exam is on Tuesday, so dave ---------------------------------------------------------------------- working with list???? You i CAN use the Edat list, the same list that is used for the static things in the calculator. [ x1 y1 ] E+ (* 'E' is sigma *) And the point is in the vector of Edat!! NO LIST JOX NEEDS! ---------------------------------------------------------------------- Have you ever used the 'LSQ' function on the HP to do traverse or level run adjustments? It seems as though all the tools are there....just how to implement them. Bill V ---------------------------------------------------------------------- I have only used it for a system of linear equations. Where I have a vector of constants on level 2. And a coefficient matrix on level 1. ?? Mike -- Michael W. Gupton Survey Technician I(II) Manitoba Hydro 19 Henlow Bay Winnipeg Manitoba mwgupton@mb.sympatico.ca mwgupton@hydro.mb.ca umgupton@cc.umanitoba.ca mgupton@mbox.rrcc.mb.ca Work: 792-1429, 474-4745, 474-3774 Pager: 932-0013 Home: 204-425-3601 ---------------------------------------------------------------------- This is the first program I have written with INFORM. %%HP: T(3)A(D)F(.); << %HELICITY ? { { Gh222 (mdeg) : } { cell path (cm): } { conc. in cell (M): } { peptide length: } } 1 { -15 .1 .0001 20 } DUP INFORM DROP EVAL DUP 5 ROLLD << (10*p*c*a)' *100/(-40000*(1- 2.57/a))' 'g*100/(-40000*(1-2.57/a))' isn't and then the whole thing is Can it be made faster and more efficient? Duncan cochran@sjh.bi.umist.ac.uk ---------------------------------------------------------------------- on comp.sys.hp48 http://www.dejanews.com/getdoc.xp?AN=440247078 But non of this hotshots on that news group have replied anything. So now im posting an extra orientation about the problem, and hope somebody have ANY idea! I have a problem on: Numeric diff solving with matrix. Look on the following thing: a simple circuit like: ____ 100ohm n1 *-----|____|----------* n2 | | | ___ 2V ___ ___ 100nf - | | | * gnd * gnd Can be represented in the equation: [[ 1/r -1/r 1 ] [[ v1 ] [[ 0 ] [ -1/r 1/r+i*w*C 0 ] * [ v2 ] = [ 0 ] [ -1 0 0 ]] [ v3 ]] [ -2A ]] Were the extra node here is a extra stamps for the 'voltage' source( it's only v1 and v2, who are interesting in the solution). The system is G*v=J! This system can be pointed up into two sq-matrix and one vector: i put G= [[ 0.01 -0.001 1 ] [ -0.01 0.001 0 ] [ -1 0 0 ] And put a new matrix for the frequency depending things: C= [[ 0 0 0 ] [ 0 0.0000001 0 ] [ 0 0 0 ]] And the current vector: J= [[ 0 ] [ 0 ] [ -2 ]] A simple solution of a AC problem is solve like this: V = J /( G + jw*C ) BUT the problem is now how do i solve for a transient analyze problem? The transient needs to be soled with a numeric diff solution!! I have lurn some methods from school two solve a diff numerically. And the form the equation has to be in is: y'=f(x,y) So in my case the diff equation is: v*G + v'*C=J (were v' is the dv/dt thing) But i can not solve out this v' , the closest i can get is this: v'*C = J - v*G C does not have any inverse matrix because it's underdefinend! What can i do???? How do i solve this?????????????????????????????????????????????????????????????????????? PLEAS HELP!! /mvh ---------------------------------------------------------------------- Vad l212ser du f232r n214got? D, Y In what bok did you hitta fr214gan? Analys i en varibel Linj212r algebra Kosan. Sorry[CenterDot]I don[AHat]t even know what language I am speaking any more ! Call it Swinglish if you will. Oh well Per and I are Swedish. Get back to me Per and Ill help ya out when you need it. Eva ---------- ---------------------------------------------------------------------- I expect no one understands the question. You have the symbol for a 2V battery driving a passive circuit made up of a resistor and a capacitor. V = I*R + Q/C or, putting I = dQ/dt (where Q is the charge on the capacitor) R*C*dQ/dt = V*C-Q. dQ/(V*C-Q) = 1/(R*C)*dt -ln(V*C-Q) = t/(R*C) + K if Q = 0 when t = 0 then K = -ln(V*C) ln(1-Q/VC) = -t/RC Q = VC(1-exp(-t/RC)) I = dQ/dt = V/R*exp(-t/RC) Alternatively, if you really mean an AC voltage source V*exp(i*w*t) then the circuit impedance is Z = R - i/(wC) I = V*exp(i*w*t)/(R-i/wC) = V/(R^2+1/(wC)^2)^0.5*(R+i/wC)*exp(i*w*t) What is the problem? Why do you need matrices and differential equations for this simple circuit? -- David Wilkinson -------------- I allredy know how to solve the transient algebraically by paper, i have made it so many times ( I'm a electronic engineer student ). I jest thought i should save the horse job for my calculator. So i have developt my own circuit simulation program on the hp48. If i find this equation for the matrix: y'= f(x,y) Then i could take out the eigenvalue of 'f(x,y)'. And that would be wery nice!! /mvh Per ---------------------------------------------------------------------- If you have the value v0:=v(t) and want v1:=v(t+delta_t), solve v1*G+(v1-v0)/delta_t*C=J(t+delta_t) for v1 and you should be done. This is called 'implicit euler method', the simplest possible method you can apply. If you happen to see a method called 'explicit euler' (which would correspond to v0*G+(v1-v0)/delta_t*C=J(t) ) - forget it. It's useless for circuit simulation for mathematical reasons, though it would be much faster if it would worked, but it doesn't work for realistic examples. Hope that helps a bit, Martin. -- Your mouse has moved. Windows must be restarted for the change to take effect. Reboot now? ---------------------------------------------------------------------- Ok.. i get it. But I was looking for a form of typing the equation like: ___________ | y'=f(x,y) | |___________| when i think about Euler it's : Y.n+1= Y.n + delta * f(X.n,Y.n) AND X.n+1= X.n+delta_t . Now when i followed you advise i get the equation: V1 = ( J(t+delta_t)+ (V0/delte_t)*C) * (G + C/delta_t)^-1 delta is found here on several places, and i can absolutely not figure out were Y.n is. So i can solve out corresponding: f(x,y) I need V' !! How would I else easy switch between different numeric algorithm that i want?? /mvh ---------------------------------------------------------------------- This is not possible, since you don't have a differential equation system but a differential algebraic one. (This means e.g. you cannot provide arbitrary initial values for all voltages) That's the one i told you to forget about! You need X.n+1= X.n+delta_t . Y.n+1= Y.n + delta * f(X.n+1,Y.n+1) (of course, you have to solve that for programming, first.) what else do you need? v1 is v(t+delta_t), which corresponds to Y_n+1 and X.n+1=t_n+delta_t As i explained above, that's not possible in general. (Otherwise C would be regular). You cannot apply methods designed for explizitly stated differential equations (y'=f(x,y)) for implicit given differential algebraic equations out of the box. What algorithms do you want? e.g. choose trapezoidal rule: then you would have to solve (v1-v0)/delta_t*C=0.5*[(J(t)-v0*G)+(J(t+delta_t)-v1*G)] for v1. If you want other algorithms, you have to adept this. (implicit Runge Kutta methods are a bit more complicate for this) Hope, that helps Martin. ---------------------------------------------------------------------- well, i'm a french guy and a wonderful beginner on HP48.... Well, i've got some programs who can only be run with XVIEW.... i've got it but, i don't know how i can install XVIEW (like a library, i think) Plz, can u help me? It will super if u say me the procedure touch per touch (because i won't understand technical words... ;) ) Thanx a lot. A bient231t, Y.S ---------------------------------------------------------------------- I'm assuming you've got XVIEW (library 1600). Put it on your stack, that is, on the first line it should say 4: 3: 2: 1: Library 1600: XVI... Then type :0: 1600 The stack should now say 4: 3: 2: Library 1600: XVI... 1: 0: 1600 Turn your calc off and then on. Screen will flicker a little. Check your library by pressing Viola! Avoir. Bart ---------------------------------------------------------------------- On the 48G, is the Memory label on the keyboard, the color turquoise on all the calculators? My son brought his G over for me to see the difference in the KBD layout between the G and the SX. Checking the Memory I noticed that the Memory label indicates the right shift instead of the left shift. By applying the right shift only brings up a different option. Are there anymore surprises like this one on the G's keyboard? ---------------------------------------------------------------------- Turquoise is right. Right shifting on the VAR key brings up a choose box interface for memory management while left shifting should bring up a menu-based interface. I don't know how this compares to the S series. ---------------------------------------------------------------------- Note that this is true for all the keys superlabeled only in turquoise. Very helpful when you get a little more advanced and want to do RECV directly instead of going through the IO form... -- ---------------------------------------------------------------------- * You program your HP48 and have never seen a real developing environment ? * You look for an easy tool for file transfer ? * You need someone managing your backups ? * You would like somebody's doing all the stupid char conversion stuff ? * And you want it all in one ? Well, have a look on the HPShell ! After 5 years of continuous development it includes now a huge list of features one would like to have while programming the HP48 or simply using it. This is a (not complete) list of it's features: ----------------------------------------------- * Multi functional Editor with Syntax highlighting, Word Wrapping, HP48 Displays, ... * File Transfer (Kermit included, ANY other protocol is also useable!) * Backup Management * DOS and HP48 Directory Management * Macros, Hotkeys, Toolbar * free defineable Toolprograms * and much more !!! The HPShell can be found online on the Web at Here you'll find a more complete list of features, screen shots and a list of download-links spread all over world. Differences to the previous verison (3.11): ------------------------------------------- This release is a pure bug fix. Source Code of the HPShell: --------------------------- With this version the source code of the HPShell is released and freely downloadable from the Internet. See -- Tom Wellige http://www.kst.dit.ie/people/twellige http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own --------------- I have Jazz library and I want to disassemble some useful commands. Can anyone help me doing that. I have a list of the rom addresses, but I don't know how to put an command in the stack without it's evaluation. Jo213o Pedro P220go http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own ---------------------------------------------------------------------- If you mean UserRPL commands, enter one or more into a list, then DIS and ED that list (recent Jazz versions will automatically DIS most objects when ED is called) For supported system objects, locate their entry in the EC catalog (scroll until the desired entry is the top entry on the screen), then press cursor-right key to start ED at that address. If you have an address alone (in the form #XXXXXh), then DOB and ED. Within ED, put the cursor on any label or symbol, or on any of the words PTR or ROMPTR or ID, and then press right-shift [+/-] to start another ED for that object; this is like clicking a browser link, in that when you exit the new session, it will go back to the previous location. ----------------------------------------------------------- ---------------------------------------------------------------------- Start with the input of these brackets: { }, While the list is open enter the desired command (in alpha mode or directly from the selected menu). When you have something like e.g. { UPDIR } apply the command HEAD on it and go on with the desired JAZZ function. Bye ---------------------------------------------------------------------- can anybody please tell me how I could bloc the hp's keyboard in a program while making it beep thanks to the SYSEVAL command ; if you also know useful commands using syseval , you you tell me also , thank you ---------------------------------------------------------------------- Has anyone noticed Erable making errors in limits that include undefined structures? I noticed Erable v3.2 made a mistake on the function 'a/(2*pi)*(((-1)^n+1)/(n^2-1))' 'n=1'. It returns 'Infinite', when the correct answer is '-(1/4*a*i)' This result is obtained by using l'Hospitals rule, and I thought that maybe someone else have had trouble finding such limits? Ice ---------------------------------------------------------------------- In Msg 79n9iu$h5$2@news.cybercity.dk, SSchmidt@vip.cybercity.dk (Ice) Hmm, what's d(-1)^x/dx? Michael -- ---------------------------------------------------------------------- It's LN(-1)*(-1)^x, which is pi*i*(-1)^x Ice ---------------------------------------------------------------------- Is the PDF documentation for ALG48 v4.2 in pretty bad condition, or is it just my printer that doesn't print it right (I have a HP DeskJet 820Cxi)? The text seems very choppy/blurry and sides on tables are not complete. It looks as if the printer is running out of toner, but this isn't the case (many other documents - including PDF - are printing just fine). Ice ---------------------------------------------------------------------- mine prints fine on a HP 5L, PCL mode. Peter Khor ---------------------------------------------------------------------- Yeah, the PDF file is really bad. However, the PS file is really good. It's prints really will with ghostview. ---------------------------------------------------------------------- No, it really appears to suck. I even took it to work and ran it through some pretty heavy duty image processing / font clean up routines - still no joy. Roger ---------------------------------------------------------------------- can anybody tell me how to bloc the keyboard and play sound while having bloqued all keys using syseval?THANKS! ---------------------------------------------------------------------- I spoke to someone about it a while back (I think it was the algorithm used for trig functions). I was told to check out the TI website, but I never made it there.. You might see if you can find anything there. -- Aaron. ---------------------------------------------------------------------- http://devil.ece.utexas.edu/ is a nice starting point ... To get out of complex mode just enter [g] [CF] 8 this clears the = flag 8 of the HP15C. (To enter complex mode you have the choice : [f] [I] or [g] [SF] 8 ) JPB I apologize for the off-track question, but does anyone out there = know how to get the HP-15C out of complex mode?=20 --=20 Albert V. Turk - X-33 Structural Dynamics & Flutter 1011 Lockheed Way, Palmdale, California 93599-2545 (805)572-6342 phone, (805)572-6327 FAX =20 ------=_NextPart_000_0078_01BE5485.4DF68E20 enter [g] [CF]=20 8       this clears the flag 8 of the=20 or [g]=20