Re: Complex Number Juxtapositions Message #2 Posted by Karl Schneider on 18 Oct 2007, 12:20 a.m., in response to message #1 by Trent Moseley
Hi, Trent 
Regarding operations with complex numbers on the HP35s:
Quote:
"So near yet so far..."
Formal response: "I concur with your sentiments."
Informal response: "Amen, brother!"
Perhaps more annoying is that SHOW also doesn't work on a complex number, and that there is no simple way to separate the components of a complex number. Thus, the RND limitation can't be circumvented by applying RND to each part separately, but even if RND did operate on a complex number, SHOW won't verify that it worked as intended...
Quote:
You can ROUND one on the 42s but you can't STORE it.
The second part of that statement is incorrect. A complex number can always be stored to a named variable, or it can be stored to a numbered register if the matrix of storage registers ("REGS") is dimensioned as complex:
RCL "REGS" (a softkey), ENTER, COMPLEX, STO "REGS"
Indeed, RND is applied to both parts of a complex number (in rectangular or polar mode) on the HP42S. If the user wants to round only one component, the number can first be separated into two reals using COMPLEX.
Try this on an HP42S: Enter a complex number with 12digit mantissas for both components (say, pi and e^1), and assemble the number in POLAR mode using COMPLEX. SHOW will then display both components with their 12digit mantissas. Then, do FIX 03, RND, and SHOW. You'll see 3.142 at angle 2.718 before and after SHOW. Change to RECT mode, and SHOW again. You'll see 12digit rectangularcoordinate values for both components, indicating that RND was properly applied to the displayed value, even though the number may have been internally represented in rectangular form all along.
 KS
Edited: 18 Oct 2007, 12:26 a.m.
