HP41 Mcode Entrypoint for 'high precision numbers'



#5

Hi,

In PPCJ-V10-N7 Charles Bouldin talks about the normal arithmetic entrypoints ADD2_10 etc. In his first paragraph he also says "... additional entry points for high precision numbers which occupy a pair of addresses exist but will not be discussed here".

Does anyone else know about this entry-points and how to use them?

Thanks!

Cheers

Peter


#6

Addresses (hexadecimal):

ad2-10   1807
ad1-10 1809
ad2-13 180c

mp2-10 184d
mp1-10 184f
mp2-13 1852

dv2-10 1898
dv1-10 189a
dv2-13 189d

Comments from the source code:

******************************************************
* common math entries ***
* if number is 2-10, ***
* then form is: ***
* A has 10 digit form ***
* C has 10 digit form ***
* if number is 1-10, ***
* then form is: ***
* A has sign and exp ***
* B has 13 digit mantissa ***
* C has 10 digit form ***
* if number is 2-13, ***
* then form is: ***
* A and B as in 1-10 ***
* M has sign and exp ***
* C has 13 digit mantissa ***
* ***
* on exit, C has 10 digit form ***
* A and B have 13 digit form ***
* ***
******************************************************

#7

Thanks Eric! Now I just have to figure out how to use them :-)

Cheers

Peter
PS: it would appear that they are not double precision but just 13 digits instead of 10, correct?


#8

Yes, 13-digit mantissa. The intent was that they provide more precision for intermediate results in calculations of the elementary functions (trig, logs, exponentials, etc). The extra 3 digits makes a big difference, though it isn't sufficient to guarantee correct rounding for all cases.


Possibly Related Threads...
Thread Author Replies Views Last Post
  HP Prime: complex numbers in CAS. Alberto Candel 1 564 12-06-2013, 02:36 PM
Last Post: parisse
  [HP Prime] Plots containing complex numbers bug? Chris Pem10 7 1,072 12-05-2013, 07:40 AM
Last Post: cyrille de Brébisson
  HP Prime numerical precision in CAS and HOME Javier Goizueta 5 769 11-16-2013, 03:51 AM
Last Post: Paul Dale
  HP-41 MCODE: The Last Function - at last! Ángel Martin 0 355 11-08-2013, 05:11 AM
Last Post: Ángel Martin
  comparing numbers on the WP 34S Kiyoshi Akima 7 955 10-19-2013, 09:28 AM
Last Post: walter b
  HP Prime: Operations with Large Numbers Eddie W. Shore 0 296 10-19-2013, 12:24 AM
Last Post: Eddie W. Shore
  HHC 2013 room numbers David Hayden 2 466 09-20-2013, 05:34 PM
Last Post: sjthomas
  [HP-Prime xcas] operations with complex numbers + BUGs + Request CompSystems 9 1,154 09-08-2013, 10:40 PM
Last Post: CompSystems
  TED Talk: Adam Spencer: Why I fell in love with monster prime numbers Les Bell 3 588 09-05-2013, 12:54 PM
Last Post: Ken Shaw
  Irrationality in numbers....the book Matt Agajanian 4 606 08-30-2013, 04:14 PM
Last Post: Matt Agajanian

Forum Jump: