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Setting the debug option

If you cannot succeed in finding the right parameters you may use the debug option and to try to understand what is going on.

The algorithms of ALIAS are in general giving some information when running. There is a debug tool with three different levels: the first one (which is the default) is user-oriented and will help you to figure out what is going on, the second one is for expert and the third one is no debug at all. To set the debug option add to your program one of the following sentence:

 
Debug_Level_Solve_General_Interval=0;
Debug_Level_Solve_General_Interval=2;
or, if you are running ALIAS from MAPLE, add to your MAPLE program one of the following line:
 
`ALIAS/debug`:=2:
`ALIAS/debug`:=0:
The value 0 indicates no debug while level 2 is the highest (1 being the default). Then, when you run your program ALIAS will print lines looking like the following one:
 
Current box (11/23,remain:13), Sol: 0 (W=0.1,73.275)
This indicate that the algorithm is dealing with the box 11 in a list that has 23 elements. Thus 13 boxes are still to be considered as the algorithm will end when all the elements in the list have been considered.

The following part Sol:0 indicates that up to now ALIAS has found 0 solutions (for an optimization problem the value you get here is the current minima or maxima).

The last element, (W=0.1,73.275) indicates that for the current box the minimal width of the intervals in the set is 0.1 while the largest width is 73.275. With these informations you may figure out what is going on in the algorithm.


next up previous contents
Next: Contents Up: Troubleshooting: ALIAS does not Previous: Crash and bugs   Contents
Jean-Pierre Merlet 2012-12-20