OpenEuphoria

Re: RNG Test: Code to generate Diehard file in Euphoria

• Posted by Irv Mullins <irv at ELLIJAY.COM> Feb 17, 2000
• 727 views

On Thu, 17 Feb 2000, you wrote:
> Irv Mullins wrote:
re:
> >>   printf(file_number,
> >>   "%04x%04x%04x%04x%04x%04x%04x%04x%04x%04x",
> >>         {final[ 1],final[ 2],final[ 3],final[ 4],final[ 5],
> >>   final[ 6],final[ 7],final[ 8],final[ 9],final[10]})
> >>
> >>   printf(file_number,
> >>   "%04x%04x%04x%04x%04x%04x%04x%04x%04x%04x\n",
> >>         {final[11],final[12],final[13],final[14],final[15],
> >>   final[16],final[17],final[18],final[19],final[20]})
vs:
 printf(file_number, fmt, final)

Everett wrote:

> Certainly, it would be theoretically faster to move the creation of fmt
> outside
> the loop, but any compiler with any kind of optimizing capability will take
> any literal like this and treat it like a constant and move it outside the
> loop.

Apparently, that is what Euphoria does. There is no measurable difference
in execution time between a using a constant or using a literal. (less than 1%)

> The use of a variable will cause the compiler to have to check the value of
> fmt every time it sees it.
> The fastest way would be to create the value and
> assign it to fmt as a constant.

One would think so, however, there is no measurable difference between
using a constant and using a sequence. Again, less than 1%.

<snip>

> This is probably a handicap of the aged and infirm programmer, but
> complexity is oft in the eye of the beholder. It might be noted, as in the
> case of COBOL, verbose does not equal complex, or even, in most cases,
> less efficient. Also, with modern editors, I didn't type any of those
> variable names but once...the rest was cut and paste. The advantage to
> being verbose, where it does not effect performance is that it offers
> the opportunity to easily alter what is written. Exception code many times
> just becomes a different coding of an explicit sequence. Where the code
> becomes large and untenable due to explicit coding, I will agree with your
> correction. Otherwise, being straightforward has it's advantages.

True again, except that the de-referencing of members of a sequence
x[1], x[2],x[3].... etc, does affect performance:  There's a 10 - 15% increase
in execution time when applied to this list of 20.

Regards,
Irv