(32S) Accurate TVM with direct solutions

[Dave Britten]

(12-30-2015 08:22 AM)Dieter Wrote:  

(12-26-2015 11:24 PM)Jeff_Kearns Wrote:  Instead of the 13 Label, 122-line program you posted, I would recommend this short (extremely ACCURATE) 38 line program that only uses 1 label, which is essentially Miguel Toro's program for the 35s...

Jeff, please take a look at the thread title: it says "Accurate TVM with direct solutions". That's the point here: Except the routine for the interest rate (which cannot be calculated directly) Dave's program returns the results immediately by direct calculation – no solver and no iterations required, and the user also does not have to provide two initial guesses.

Maybe the program even is a tiny bit more accurate since it seems to include implementations of both an e^x–1 and a ln(1+x) function, while the version you suggested only does the latter.

So both versions have their benefits. Yours is very short and compact while Dave's is faster and returns directly calculated results immediately.

Dieter

Right, this one is built for speed (which is often important when making quick financial decisions). As such, it makes quite a few sacrifices on size. I do have a one-label solver-based version kicking around for when I only need to run a few numbers, and don't want to type in a large program. Or better yet, I just grab my 17BII.