Looking for TVM contributions

[dm319]

Ok these are the current rankings.
More results are very warmly welcome!

Code:


| calculator      | 1   | 1b  | 2   | 3   | 4   | 5   | 6   | 7   | 8   |
|-----------------|-----|-----|-----|-----|-----|-----|-----|-----|-----|
| Plus42 1.1.9    | -29 | -32 | -28 | -18 | -∞  | -30 | -31 | -26 | -35 |
| NSTK TVM V5     | -29 | -30 | -28 | -18 | -10 | -30 | -31 | -19 | -30 |
| TI-83 Plus      | -10 | -12 | -8  | -7  | -∞  | -11 | -11 | -19 | -18 |
| RPN83P v0.9.0   | -9  | -12 | -9  | -7  | -∞  | ERR | ERR | -11 | -12 |
| HP-12cp         | -8  | -10 | -6  | -6  | -13 | ERR | ERR | -21 | -11 |
| Casio FC-200    | -6  | -8  | NA  | -4  | -13 | ERR | ERR | -19 | -9  |
| HP-80 (HP-1973) | -6  | -4  | -5  | 5   | ERR | ERR | ERR | ERR | ERR |

I have shown the exponent value to which the result is congruent with the most accurate result. I.e. -5 means it is accurate to 0.00001 and 3 means accurate to nearest 1000. I'm thinking there are other metrics - ergonomics, preference for returning a positive I%YR, or ability to return an I%YR result without providing guesses, and ability to fail gracefully for unsolvable problems, but these are more subjective, so will leave that for the moment.

EDIT1: used some adapted plus42 code running in arbitrary precision in R using the Rmpfr package as a source of truth. This has boosted the numbers for Plus42 further!