Fwd: Re: [Help-glpk] MySQL Support for GLPK 4.23

[Andrew Makhorin]

Hi Heinrich,

Thank you for your efforts.

I think the table feature is too sophisticated. Probably it is
reasonable to have it in AMPL, which is a more or less full-featured
programming language (unlike its earlier versions). However, I would
like to keep MathProg being a declarative, not procedural language.

So it seems to me that it would be sufficient to implement the
following two statements: read and write.

The read statement is the following:

   read s, p1, p2, ..., pn from <data definition> ;

where s is a set (may be omitted), p1, p2, ..., pn are parameters,
<data definition> defines a text file, select query, etc. It is
assumed that data for this statement is coded as a table:

   i11 i12 ... i1m v11 v12 ... v1n
   i21 i22 ... i2m v21 v22 ... v2n
   . . .

where (ik1, ik2, ..., ikm) is m-tuple, which being read is added to
set s and used as index for corresponding parameters, vk1, ..., vkn
are values of parameter members.

The write statement is similar to the printf statement:

   write {...} e1, e2, ..., en to <data definition> ;

where e1, e2, ..., en are expressions.

What do you think about this?


Best regards,

Andrew Makhorin