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Full Version: [WP34S] Once Working TVM Now Broken
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The TVM library routine was working very well thanks to improvements to the solver, but when I revisited tonight for the first time in a couple of weeks it throws an "Out of Range" error whereas once it gave a correct result.

My test problem is basically a mortgage of PV = 153295, FV = 0, PMT = -976.25, with N = 300, NP = 12, NI = 2. The correct interest rate is around 5.95%/yr, which the program used to spit out to high accuracy. Now the solver proceeds very quickly to the error noted.

I'm baffled. I am using the latest version, and I can produce this on the real calc and the emulator.

Just thought I would share this to see if anyone else can reproduce it.


Edited: 7 May 2012, 4:50 p.m. after one or more responses were posted

The solver itself is broken in general.

Attempting to solve even the basic x^2-2 = 0 equation with guesses 1.4 an 1.42 on the stack generates the Out of Range error.

Hope this helps,


We'll have a look.

Edit: I did have a look. My shame. :-(

I wonder why this hadn't surfaced earlier. It was a typical "always" against "never" programming mistake.

Edited: 7 May 2012, 3:24 a.m.

Glad it was fixed. Looking at the SVN comment I am surmising it was a a pretty basic issue that could have implications whenever POPUSR was called in XROM.

Nice to see my beloved TVM back to normal.


Glad you like it. Was hard work to get it in the function set over a year ago :-)

Glad you like it. Was hard work to get it in the function set over a year ago :-)

And whose work was it?

Yours. Appreciated!

WP 34S is a real group effort. :-)