In last installment, the Casio overclocking utility Ftune2 improved the speed performance of a Nelder-Mead program by 4.5 times. For standard calculations, more impressive results are obtained from this nice utility. In this test, the standard normal distribution function is applied in the Casio fx9860GII Equation Solver and the task is to find the Z variable (as “T” in the below screen), given the cumulative probability distribution of 0.9 (as “A” in the below screen).
In other words, the solver’s task is to find Z from the given area of 0.9 as shaded in the below chart, which is obtained for verifying the solver’s result of 1.28155156 using the command
And here is the result on speed performance:
00:38 No overclocking, back-lit OFF
00:40 No overclocking, back-lit ON
00:06 Overclocked 265.42 MHz, USB OFF, back-lit OFF
00:07 Overclocked 265.42 MHz, USB OFF, back-lit ON
00:05 Overclocked 265.42 MHz, USB ON, back-lit OFF
00:05 Overclocked 265.42 MHz, USB ON, back-lit ON
The performance gain by overclocking is 7.6 to 8 times, depending whether the back-lit is on for non-overclocked runs.
For the same equation solving by the TI Nspire using
nsolve(), it took 01:30 to return a result of 1.28155156555.
However, using the built-in standard functions
NormCD() for the Casio and
normCdf() for the TI as below
Casio fx-9860GII A=NormCD(-999,T) TI Nspire nsolve(normCdf(-∞,x,0,1)=0.9,x)
both units return results instantaneously (Nspire returns 1.28155193868 while Casio returns 1.281551566).