Thank you for your comments.  I have indeed upgraded Maple to 11.02.

I've done some more experiments and discovered the following:  the problem does not occur with Mac OS 10.6.4, but it does occur with Mac OS 10.6.5 (the latter being the most recent release of the Macintosh operating system). This was tried on the same machine (a MacBook), so it really is a problem with the operating system---I don't think that any blame can be laid at the door of Maple.  [OS 10.6.5 has also introduced a more serious problem, which is a wireless networking problem that as yet does not seem to have been fixed.]

Since it really is useful to be able to get feedback from a (long) procedure whilst it is executing, I think the only think that one can do is to include a few readline(); statements into the body of the loop. This means that one has to hit the return key for the procedure to continue, but at least one is getting some kind of feedback as it progresses.

Thank you very much for your time and help.

Thank you for your comments.  I have indeed upgraded Maple to 11.02.

I've done some more experiments and discovered the following:  the problem does not occur with Mac OS 10.6.4, but it does occur with Mac OS 10.6.5 (the latter being the most recent release of the Macintosh operating system). This was tried on the same machine (a MacBook), so it really is a problem with the operating system---I don't think that any blame can be laid at the door of Maple.  [OS 10.6.5 has also introduced a more serious problem, which is a wireless networking problem that as yet does not seem to have been fixed.]

Since it really is useful to be able to get feedback from a (long) procedure whilst it is executing, I think the only think that one can do is to include a few readline(); statements into the body of the loop. This means that one has to hit the return key for the procedure to continue, but at least one is getting some kind of feedback as it progresses.

Thank you very much for your time and help.

I think that this is a Mac issue:  First, I have been using Worksheets throughout. Second, on another Mac running OS 10.4.11, the phenomenon does not occur (again using Worksheet mode throughout).

I think that this is a Mac issue:  First, I have been using Worksheets throughout. Second, on another Mac running OS 10.4.11, the phenomenon does not occur (again using Worksheet mode throughout).

Here is a very simple example:  If I enter

   for i to 10 do print(i,evalf(int(int(1/(1+x^2+y^2)^i,x=0..1),y=0..1)));od;

in the GUI version of Maple 11 under Mac OS 10.6.5, the sequence of results will not be printed until the last calculation is performed.  However, if I enter the same command in the command line interface of Maple 11 using the same computer, the sequence of results is printed out as each calculation is performed.

The procedure itself is irrelevant here---I've simply chosen integrals to slow maple down.  But the reason why it would be useful to have Maple printing the results as it computes them is that it makes debugging a lot easier when dealing with prodecures that really do take a Maple a long time to compute.

Many thanks for your interest and help.