Re: [Help-glpk] Database connectivity in MathProg

[Andrew Makhorin]

> I tried to use it in the appended example and received the following
> output:

> Reading model section from sudoku_csv.mod...
> Reading data section from sudoku_csv.mod...
> 75 lines were read
> Reading ti...
> GLPK internal error: dca->type[k] != '?'; file glpmpl03.c, line 4846

> Could, You, please tell me how to correct the model or the csv file.

There must be a diagnostic message saying that some filed is missing
in the csv file. I detected that only to-day morning.

In your csv file there are three fields named LIN, COL, VAL (btw,
spaces between fields are *not* ignored, so you should remove them).
However, in the table statement:

table ti IN 'CSV' 'sudoku_in.csv' :
  fields <- [COL, LIN], givens;

you did not specify a field name for givens (by default the field
name is the same as the name of corresponding parameter). The correct
statement might look like follows:

table ti IN 'CSV' 'sudoku_in.csv' :
  fields <- [COL, LIN], givens ~ VAL;

Please see the example I've just posted to the list.