HP Forum Archive 17

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Some fun during lunch Message #1 Posted by Miguel Toro on 27 July 2007, 7:15 p.m. Reading complains about the 35s unable to separate real and imaginary parts from a complex number, I made these little and unambitious programs to "help" get them apart and to try some of the new features. Usage: 1.- execute the program 2.- Enter complex number as xiy - R/S --> now you see the number in polar mode 3.- Enter angle - R/S --> you see the number in polar mode again 4.- Enter radius - R/S --> you get both x and y separated. With programs A and B, they are in the X and Y registers, with program C you get a vector. Program A A001 LBL A A002 STOP A003 r@a (polar mode) A004 STOP A005 x<>y A006 STOP A007 REGZ A008 SIN A009 x<>y A010 * A011 LASTx A012 REGT A013 COS A014 * A015 xiy (rectangular mode) A016 RTN LN=56 Program B B001 LBL B B002 STOP B003 r@a B004 STOP B005 x<>y B006 STOP B007 ENTER B008 REGY * SIN(REGT) B009 REGY * COS(REGT) B010 xiy B011 RTN LN=61 Program C C001 LBL C C002 STOP C003 r@a C004 STOP C005 x<>y C006 STOP C007 [REGX*COS(REGZ),REGX*SIN(REGZ)] C008 xiy C009 RTN LN=58 note: I am having fun like a little kid :-) Well, pure RPN is smaller and faster (but speed does not really matters here) and this could be just the spark for someone to write a "real" converter. Regards, Miguel

P->R and R->P on the HP35s Message #2 Posted by Reth on 27 July 2007, 10:10 p.m., in response to message #1 by Miguel Toro Well this is my first attempt to deal with that problem :) I'm waiting for a real converter too My program label S is dedicated for subroutines and here are the first ones: S001 LBL S S002 GTO S004 S003 GTO S015 S004 X<>Y S005 SIN S006 X<>Y S007 LASTx S008 COS S009 X<>Y S010 * S011 X<>Y S012 LASTx S013 * S014 RTN S015 i S016 * S017 + S018 ABS S019 LASTx S020 ARG S021 360 ; optional, to get angles between 0 and 360 S022 RMDR ; optional, to get angles between 0 and 360 S023 X<>Y S024 RTN If not obvious, XEQ S002 is equivalent of theta,r -> x,y on the HP-33s and XEQ S003 - of x,y -> theta,r Cheers, Reth

Re: P->R and R->P on the HP35s Message #3 Posted by Les Wright on 28 July 2007, 12:43 a.m., in response to message #2 by Reth Reth, I think your steps S002 and S003 are redundant. Take those out, and everything moves up two lines. One can call the polar->rect conversion with XEQ S001, or simply XEQ S ENTER, and the other conversion with XEQ S013. This may even speed things up very slightly. Les

Re: P->R and R->P on the HP35s Message #4 Posted by Reth on 28 July 2007, 1:40 a.m., in response to message #3 by Les Wright Sure Les, even XEQ S002 would do for the P->R routine reducing steps by 1 ;). I'm just trying to create permanent addresses for frequently used routines as list grows up for the expense of a few more bytes. thanks and best regards, reth

Re: Some fun during lunch Message #5 Posted by Les Wright on 28 July 2007, 12:37 a.m., in response to message #1 by Miguel Toro Miguel, I think that everyone here with a 35s is eventually going to need a short fast subroutine that returns the Re and Im parts of complex number. I have come up with one that does it in 14 or so steps, but I don't want to put it here yet because I really believe it can and should be briefer and faster. Fortunately, taking Re and Im components from the stack to create a complex number is much easier to program--a program with the equation REGY + i*REGX is just one way to do it. One thing I do like--one has a choice of how one enters complex numbers on the 35S irrespective of whether one is in xiy or r@a mode, since both the i and @ keys are right there to choose from. Even on the 42s, the behaviour of a ENTER b COMPLEX is contingent on angle mode and whether one has set RECT or POLAR. I sometimes find this a nuisance. I don't like ALG mode so I can't comment on x+iy mode with much intelligence. Any takers out there regarding the smallest and fastest subroutine that returns the Re and Im parts of a complex number? Les Edited: 28 July 2007, 12:38 a.m.

Re: Some fun during lunch Message #6 Posted by Les Wright on 28 July 2007, 4:39 a.m., in response to message #5 by Les Wright Hi there, this is the shortest I have been able to come up with (at least the shortest in strict RPN). I would like to know if there are shorter and faster ways of decomposing a complex number to Re and Im parts LBL I ENTER ABS X<>Y ARG SIN LASTx COS REGZ * X<>Y REGZ * RTN Works simply. Place xiy (or the equivalent r@a) on the stack. XEQ I ENTER. And you get x in the Y register and y in the X register, just as though one executed COMPLEX on a complex number in rectangular mode on the 42S. There is an annoying vulnerability to occasional rounding error. For example when executing the routine on 5i13, I get 5.00000000001 for the real part. If there is a work around for this I would be grateful. I want to blame the cosine bug, but since Arg(5i13) is approximately 70 degrees, and nowhere near the troublesome range between 89 and 90 degrees, I don't think it is the culprit in this example. Les Edited: 28 July 2007, 5:07 a.m.

Re: Some fun during lunch Message #7 Posted by Reth on 28 July 2007, 5:18 a.m., in response to message #6 by Les Wright Hi Les, that's shorter ;) LBL I ABS LASTx ARG SIN LASTx COS REGZ * X<>Y REGZ * RTN that's shorter too and doesn't depend on flag 10 :) LBL I ABS LASTx ARG SIN LASTx COS ENTER R^ * R^ R^ * RTN to get rid of that 5.00000000001 I'd set the HP35s to say FIX 9 and then do RND after multiplications and finish with ALL Cheers, Reth

Re: Some fun during lunch Message #8 Posted by Miguel Toro on 28 July 2007, 5:37 a.m., in response to message #6 by Les Wright Les, You do not really need the first ENTER. Here: I001 LBL I I002 ABS I003 LASTx I004 ARG I005 SIN I006 LASTx I007 COS I008 REGZ I009 * I010 x<>y I011 REGZ I012 * I013 RTN Just one step shorter. Miguel Done! Edited: 28 July 2007, 10:06 a.m. after one or more responses were posted

Re: Some fun during lunch Message #9 Posted by Les Wright on 28 July 2007, 6:10 a.m., in response to message #8 by Miguel Toro Take out what you have called step I005 and correct the numbering and I think it is right. Les

Re: Some fun during lunch Message #10 Posted by Ren on 31 July 2007, 11:14 a.m., in response to message #1 by Miguel Toro 20070731 Hmmm, I am a loooonnnngggg way from considering programming a calculator a "fun lunch" activity! I guess that is why I'm only ranked "Geek, 3rd Class (G3C)" B^) Ren dona nobis pacem P.S. keep up the good work!

Re: Some fun during lunch Message #11 Posted by Miguel Toro on 31 July 2007, 1:05 p.m., in response to message #10 by Ren Please, Do not call me geek in from of my children (Irene, the older, has read this message while I was looking at it): they still think that I am cool. ;-) Miguel

Re: Some fun during lunch Message #12 Posted by Les Wright on 1 Aug 2007, 11:57 p.m., in response to message #11 by Miguel Toro Geek is the new cool. Haven't you heard? ;)

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