Re: complexity of numerical software(2)

Richard Fateman wrote: 
Jaap Spies wrote:

???I don't know where this enumeration problem came up,
but in my view it is not "numerical software" in the
sense of "numerical analysis".  Combinatory enumeration
has its interesting aspects, but to say, based on this
example, that numerical software is easy (or hard) doesn't
seem convincing.
RJf



Do something to proces alle n-subsets of a m-set.


 > problem(int n, int m)
 > {
 >     int i, j;


RJF

May be I stretched the meaning of numerical software a little
to far. At best it is seminumerical, but I did not have an example of well documented code at hand to make my point with true numerical sofware.
For classical problems you don't have to invent the wheel. So even
mediocre programmers can write perfect code when they copy (or folow)
Knuth's TAOCP, 'Numerical Recipes' or some other accepted standard.

Programmers make there mistakes especially when they are not well
educated or left alone with their problems.
A problem may look difficult, but in most cases someone else solved
it for (and before) you.

This newsgroup is sci.math.symbolic so it is possibly not the right
place to discuss numerical software at all.

Counting lines in software production is not what it used to be:
In Maple for instance the example reduces to:
> with(combinat):
> s:=choose({1,2,3,4,5,6,7},5);

s := {{1, 2, 3, 4, 5}, {1, 2, 3, 4, 6}, {1, 2, 3, 4, 7}, {1, 2, 3, 5, 6},
  {1, 2, 3, 5, 7}, {1, 2, 3, 6, 7}, {1, 2, 4, 5, 6}, {1, 2, 4, 5, 7},
  {1, 2, 4, 6, 7}, {1, 2, 5, 6, 7}, {1, 3, 4, 5, 6}, {1, 3, 4, 5, 7},
  {1, 3, 4, 6, 7}, {1, 3, 5, 6, 7}, {1, 4, 5, 6, 7}, {2, 3, 4, 5, 6},
  {2, 3, 4, 5, 7}, {2, 3, 4, 6, 7}, {2, 3, 5, 6, 7}, {2, 4, 5, 6, 7},
  {3, 4, 5, 6, 7}}
> proces(s,5,7);

This can be written as a oneliner.

Jaap Spies
.

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