[WP34S] Once Working TVM Now Broken

[Les Wright]

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.

Les

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

[Les Wright]

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,

Les

[Marcus von Cube, Germany]

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.

[Les Wright]

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.

Les

[Walter B]

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

[fhub]

Quote:

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

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And whose work was it?

[Marcus von Cube, Germany]

Yours. Appreciated!

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