HP 42S Version Speed Variation

[Mike Morrow]

(06-11-2014 02:31 PM)Gerald H Wrote:  My laziest conclusion is that the short loop tests do not in any way really stress the calculator, whereas the factorization does.

One may obtain grossly different relative speeds of calculation depending on the benchmark used. I can use the simple loop benchmark and show that Free42 on my Android is 8000 times faster than a real HP 42S, or I can use the Savage Benchmark and show that Free42/Android is a mere 400 times faster than a real HP 42S! The simple loop benchmark is a fool's benchmark. Nor do I like the pointlessly popular N-queens benchmarks...they do not produce valid comparison results for scientific-oriented calculations.

For many years (more than 30 years ago) the Savage Benchmark was commonly used to test a PC's compiler or interpreter speed and accuracy and the effects of improved hardware like a faster clock or math co-processor addition, or an alteration of precision. A process that made heavy use of common scientific functions and their inverse functions is the most useful benchmark for scientific evaluation. The Savage Benchmark remains rather useful today for scientific calculators.
Radian mode. X=0. Perform next line 2500 times:
X = tan(atan(e^(ln((sqrt(X+1))^2))))
The time it takes to complete 2500 iterations is a benchmark for speed.
The amount that the end result varies from a perfect 2500.0000000 is a benchmark for accuracy.

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NB: There is a slightly different version of the Savage Benchmark that is flawed in construction, compared to that described above and programmed below. The flawed construction was forced by limitations of BASIC language structure in standard interpreters or compilers that made it easier to program this Savage version:
Radian mode. X=1. Perform next line 2499 times:
X = tan(atan(e^(ln((sqrt(X^2))))) + 1

Calculator language structure (even TI's) is much more flexible and need not utilize the flawed construction.
***

For the HP 42S, here is a version of the Savage Benchmark:

01 LBL "SB"
02 RAD
03 0
04 LBL 01
05 1
06 +
07 SQRT
08 X^2
09 LN
10 E^X
11 ATAN
12 TAN
13 DSE ST Y
14 GTO 01
15 BEEP
16 DEG
17 END

Enter "2500" in X, push "SB" and start external timing device.

RESULTS:
Rev A ROM HP 42S (2934Sxxxxx): 2499.99946106 in 591 seconds.
Rev C ROM HP 42S (3328Sxxxxx): 2499.99946106 in 609 seconds.

The numerical results are identical. The speed result difference is negligible...all that can be concluded is that this particular ROM A machine is 3 percent faster than this particular ROM C machine.