41CL Quiz: Determinant of 30x30 antiIdentity matrix

05112018, 09:10 AM
(This post was last modified: 05112018 09:11 AM by Ángel Martin.)
Post: #1




41CL Quiz: Determinant of 30x30 antiIdentity matrix
This quiz is just for you, proud owners of a 41CL: 
Calculate the determinant of a 30x30 matrix with all elements equal to "1" except the diagonal, which has all zeros. I call this type "antiIdentity", but it's totally made up for you purists out there so don't nail me down just yet. The exact result is Det = 29 My solution returns 28.999999977 in 11 minutes, give or take... Hint: check in the CL Library for a suitable aid... Cheers, ÁM 

05112018, 06:06 PM
Post: #2




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05112018 09:10 AM)Ángel Martin Wrote: This quiz is just for you, proud owners of a 41CL:  Sorry, Ángel, you know I couldn't resist ... Quote:Calculate the determinant of a 30x30 matrix with all elements equal to "1" except the diagonal, which has all zeros. I call this type "antiIdentity", but it's totally made up for you purists out there so don't nail me down just yet. I know, I know, this is just for the 41CL but nevertheless here's the result for the HP71B under JF Garnier's Emu71. From the command line: >DESTROY ALL @ OPTION BASE 1 @ DIM A(30,30),C(30,30) >MAT A=CON @ MAT C=IDN @ MAT A=AC @ DET(A) 29.0000000001 The timing is 0.15 seconds, give or take a hundredth ... Have a nice weekend and best regards. V. 

05112018, 07:34 PM
(This post was last modified: 05112018 07:39 PM by Ángel Martin.)
Post: #3




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05112018 06:06 PM)Valentin Albillo Wrote:(05112018 09:10 AM)Ángel Martin Wrote: This quiz is just for you, proud owners of a 41CL:  Not a problem Valentín  I'm very glad you chimed in. Ah the beauty of Saturn MCODE, I'm sooo jealous of such sheer power ;) The original goal of this exercise was to show that it's possible to deal with 900 element matrices using the expanded registers on the CL board. Obviously the bottleneck here is the FOCAL program that calculates the determinant. I'm toying with the idea of modifying the MCODEbased functions in the Advantage to also support the Yregisters, but it's a tall order... Saludos y buen finde. ÁM. PS. I'm curious to know: does EMU71 run faster than the real machine (being a PC application), or it also emulates the Saturn CPU speed? 

05112018, 07:48 PM
(This post was last modified: 05112018 07:49 PM by John Keith.)
Post: #4




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
OK, more cheating. HP 50g, exact mode:
Code:
Result: 29 Physical calculator: 61 seconds. Emulator: 2.17 seconds. I'm sure the Prime would be much faster but I don't have mine handy. John 

05112018, 08:04 PM
Post: #5




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05112018 07:34 PM)Ángel Martin Wrote: PS. I'm curious to know: does EMU71 run faster than the real machine (being a PC application), or it also emulates the Saturn CPU speed? No, it runs much faster, some 200x240x faster on the 18yo 32bit singlecore XP box I use to run it. Frankly, I don't see the point of emulating the original speed, as it's the case with the old version of the Nonpareil emulator I have, which does just that and so sees very little use. Buen finde y saludos. V. . 

05112018, 08:41 PM
Post: #6




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05112018 07:34 PM)Ángel Martin Wrote: The original goal of this exercise was to show that it's possible to deal with 900 element matrices using the expanded registers on the CL board. Obviously the bottleneck here is the FOCAL program that calculates the determinant. I'm toying with the idea of modifying the MCODEbased functions in the Advantage to also support the Yregisters, but it's a tall order... Gene: My mind went to the Yregisters applications rom right away (rom ID 21). The PPC matrix functions and the JMB are in there in FOCAL. Will love to see what the YRRM program does at 50X on this. MUCH slower than Valentin's solution though. :) 

05122018, 02:50 AM
(This post was last modified: 05122018 03:01 AM by Joe Horn.)
Post: #7




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05112018 07:48 PM)John Keith Wrote: OK, more cheating. HP 50g, exact mode: Prime in CAS view: det(makemat(1,30,30)IDENMAT(30)) Result: 29 Physical calculator (HW rev C): 0.041 seconds Emulator: around 0.00224 seconds EDIT: The 50g's approx mode is much faster than exact mode in this case. If the input is a matrix of reals (TYPE 3) instead of a symbolic array of integers (TYPE 29), DET returns 29.0000000000 in 14.17 seconds. <0ɸ0> Joe 

05122018, 05:21 AM
(This post was last modified: 05122018 08:56 AM by Ángel Martin.)
Post: #8




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
First, thanks John, Joe & Valentín for your inputs  cheating perhaps, but definitely worth it ;) Obviously there's no color in comparing a PC emulator speed with a real machine  but I agree the emulators that mimic the real speed fall short of delivering what they should...
Now let's come back to the snailworld for a while, should we. (05112018 08:41 PM)Gene Wrote: Gene: My mind went to the Yregisters applications rom right away (rom ID 21). The PPC matrix functions and the JMB are in there in FOCAL. Will love to see what the YRRM program does at 50X on this. MUCH slower than Valentin's solution though. :) And your mind is going to the right place  I guessed you'd make the connection, eagleeyed as you are ;) Here's the detailed description of the solution. 1. We need the CLExpanded Memory and the YREGS Apps ROMS plugged in the CL. Their mnemonics are XPMM and YRGA, just use the function PLUG to configure the MMU. Each of these two is a 4k ROM, thus two pages will be used. 2. Unless you feel like entering the 900 elements by hand (ouch!), we also need a short data entry routine to build the test matrix. The code snippets below take care of it, and I've also thrown in another short one to create an identity matrix (the opposite to our test case, i.e. an AntiAntiIdentity ;=O The two routines we'll use are YONE  to create a matrix with all ones, and YZDG, to Zero the diagonal elements of a matrix. They can be chained so just press R/S after YONE to complete the task  or use them individually if you prefer). 3. With the routines loaded in RAM we can execute the order: Remembering that the matrix control words are of the form bbb.eeerr, we type: 1.90030, XEQ "YONE", R/S, CF 00, 30, XROM "YDET" => 28.999999977 That's all there's to it  at least the command line here is comparable in size with those in the ultrapowerful universes shown by Valentín, John and Joe, I'd love to hear other options you have in mind  specially faster ones  perhaps using other DETerminant programs as I hinted at in a previous post. Code: 1 LBL "YONE" Code: 1 LBL "YIDN" Best, ÁM 

05172018, 09:58 AM
Post: #9




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
Disclaimer: please take this with the humour it's meant to be. I mean no meanness.
Just to rub salt in the wounds of all the HP owners (except perhaps for the Prime users), my 9750gII took 22 seconds to calculate the determinant of the antiidentity matrix. Mind you, it took me nearly twelve minutes to input the silly thing because I can't automatically generate an antiidentity matrix. But I thought that was pretty good calculation speed. Now back to the subject at hand... It's interesting to see the little secrets hidden away in the bowels of HP's ROM files, especially ones that had their foundations way back in the late seventies. I wonder where—and when—the functions from my calculator originated from? (Post 221) Regards, BrickViking HP50g Casio fx9750G+ Casio fx9750GII (SH4a) 

05172018, 01:55 PM
(This post was last modified: 05172018 01:59 PM by Claudio L..)
Post: #10




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05112018 07:48 PM)John Keith Wrote: HP 50g, exact mode: (05122018 02:50 AM)Joe Horn Wrote: Prime in CAS view: det(makemat(1,30,30)IDENMAT(30)) The 50g can do slightly better... newRPL with numbers in the matrix: 0.426 sec (result = 29 exact if matrix elements were exact) newRPL with symbolic numbers: 2.589 sec (more comparable to using the CAS mode in the Prime, result = '29' symbolic) So the Prime CAS is roughly 30 times more efficient than newRPL at working with symbolic expressions... there's a lot of work for me to do in that department. EDIT: P.S.: Sorry for polluting this thread, it felt like a continuation of the other antiidentity thread. 

05172018, 04:55 PM
Post: #11




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
Just curious, why you can't automatically generate an antiidentity matrix?
I created the antiidentity matrix by using small program. casio fx9860g slim: 29 in 29 seconds casio fxcg50: 29 in 6.57 seconds 

05172018, 10:36 PM
(This post was last modified: 05172018 11:21 PM by brickviking.)
Post: #12




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05172018 04:55 PM)klesl Wrote: Just curious, why you can't automatically generate an antiidentity matrix? Could you post that 9860 program here, or perhaps in "Not Remotely HP" subforum? I might keep an eye out for it, as it took me nearly 12 minutes to enter it by hand. I've done filling lists automatically, but not matrices. Annoyingly, my 9750g+ can't work with a matrix that large. It can create the initial matrix, but there's not enough memory left over to work with it unless I removed the other programs I've got installed. 9750gII: 29 in 20.5 seconds (without any speedups), 4 seconds (sped up to max) (Post 222 (111x2, (55+55+1)*2, ...) Regards, BrickViking HP50g Casio fx9750G+ Casio fx9750GII (SH4a) 

05182018, 03:47 AM
Post: #13




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05112018 07:48 PM)John Keith Wrote: OK, more cheating. HP 50g, exact mode: Even more cheating. HP 50g, approximate mode; 30 « 1.  1. OVER ^ * » EVAL Result: 29 Physical HP 50g: 0.015 seconds, give or take... :) 

05182018, 05:50 AM
Post: #14




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05172018 01:55 PM)Claudio L. Wrote: The 50g can do slightly better... newRPL is impressive! I appreciate its creation Claudio. 

05182018, 06:48 PM
(This post was last modified: 05182018 06:50 PM by hibiki.)
Post: #15




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
I see that the solution is 29 or 29 depending on whether the diagonal of 0's is descending from left to right or ascending. But my curiosity is why a simple sum or subtraction of a string of 1's (integers) multiplied 29 times and accumulated 29 times resulted in a non integer number in some responses.
My calcs: HP12C, HP15C, HP17BII+, HP20S, HP20B, HP32SII, HP34C, HP35S, HP42S, HP48GX. 

05182018, 09:13 PM
(This post was last modified: 05182018 09:14 PM by Valentin Albillo.)
Post: #16




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05182018 06:48 PM)hibiki Wrote: Iut my curiosity is why a simple sum or subtraction of a string of 1's (integers) multiplied 29 times and accumulated 29 times resulted in a non integer number in some responses. The exact determinant of an allinteger matrix is always an integer, mathematically, but the algorithms used by many nonCAS models involve divisions by pivot elements and this may introduce nonexactness in the final result. V. . 

05182018, 09:39 PM
Post: #17




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
A test of accuracy could be to see for machines that can do this calculation...
What size matrix is the level at which the answer is a noninteger for the first time. Then ... what caused it to be a noninteger? 

05182018, 10:58 PM
Post: #18




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05182018 09:39 PM)Gene Wrote: A test of accuracy could be to see for machines that can do this calculation... It's not only a function of matrix size but also of its elements, you can get a noninteger determinant even for some 2x2 specific matrix. And I already said in the previous post what causes it: division by some pivot(s) which result in nonexact quotients. Regards and have a nice weekend. V. . 

05182018, 11:02 PM
Post: #19




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
Matrix maths is a bit beyond me, at least until I delve back into the basic concepts again. The last time I dealt with matrices was way way back in my secondary school years back in the early eighties. So terms like determinant and identity are rather lost on me, though I now know what an identity matrix is. No doubt I'll have to go look up simple references for the rest of the material.
[Post 224] Regards, BrickViking HP50g Casio fx9750G+ Casio fx9750GII (SH4a) 

05192018, 12:33 AM
Post: #20




RE: 41CL Quiz: Determinant of 30x30 antiIdentity matrix
(05182018 10:58 PM)Valentin Albillo Wrote:(05182018 09:39 PM)Gene Wrote: A test of accuracy could be to see for machines that can do this calculation... Thanks Valentin. I should have said for these matrices as specified here. Some with only the 0 and 1 elements which **ought** to be an integer answer are getting round off with 0 and 1's. Can we really have a pivot that isn't a 0 or 1 in this case? Apparently! :) 

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