Hi Paul,

The code is a solution to your problem of too much output too fast. I guess M10 is more efficient than M9. An alternative solution is to make the program self-regulating, i.e. count the solutions before printing anything. If there are too many, Abort[].

Douglas

Ok I have made the list using Table, the section of program that looks through the list and finds solutions still waits till it has found all solutions first before it prints them out.

list = Table[{i^3, j^3, i^3 + j^3}, {i, 1, 1000}, {j, i + 1, 
   1000}]; list = Partition[Flatten[list], 3]; list = 
 SortBy[list, #[[3]] &]; 
Do[If[list[[q, 3]] == list[[q + 1, 3]], 
   Print[TextCell[
     Row[{ExpressionCell[list[[q, 1]]]^3, "+", 
       ExpressionCell[list[[q, 2]]]^3, " = ", 
       ExpressionCell[list[[q + 1, 1]]]^3, "+", 
       ExpressionCell[list[[q + 1, 2]]]^3, " = ", 
       ExpressionCell[list[[q, 3]]]}]]]], {q, 1, 
   Length[list] - 1}] // Timing

That is smaller than the previous program but still shows the effect. just do this simple program and see if it delay prints.

Do[Print[n, "  ", n^2], {n, 1, 1000}]

even that waits till its finished all 1000 before it prints the first. That's my concern if i was to say print 1 to 1000000 it wouldn't print anything till all had been done in memory first.

Paul

Just noticed a slight error in the code, here is a revised version, it needed a cube root inserting.

nb = CreateWindow[];
list = Table[{i^3, j^3, i^3 + j^3}, {i, 1, 100}, {j, i + 1, 100}];
list = Partition[Flatten[list], 3];
list = SortBy[list, #[[3]] &];

Do[If[list[[q, 3]] == list[[q + 1, 3]], 
  SelectionMove[nb, After, Notebook];
  NotebookWrite[nb, 
   ToBoxes[TextCell[
     Row[{ExpressionCell[Power[list[[q, 1]], (3)^-1]]^3, "+", 
       ExpressionCell[Power[list[[q, 2]], (3)^-1]]^3, " = ", 
       ExpressionCell[Power[list[[q + 1, 1]], (3)^-1]]^3, "+", 
       ExpressionCell[Power[list[[q + 1, 2]], (3)^-1]]^3, " = ", 
       ExpressionCell[list[[q, 3]]]}], "Text"]]]], {q, 1, 
  Length[list] - 1}]

Paul.

Very nice. MakeBoxes has a small problem. Gets a message "An improperly formatted directive with head Cell was encountered."

Here is an approach which will put your output results into a new notebook, saving you the need to do select and delete in your original notebook:

   nb = CreateWindow[];
   list = Table[{i^3, j^3, i^3 + j^3}, {i, 1, 100}, {j, i + 1, 100}];
   list = Partition[Flatten[list], 3];
   list = SortBy[list, #[[3]] &];

   Do[If[list[[q, 3]] == list[[q + 1, 3]], 
     SelectionMove[nb, After, Notebook];
     NotebookWrite[nb, 
      ToBoxes[TextCell[
        Row[{ExpressionCell[list[[q, 1]]]^3, "+", 
          ExpressionCell[list[[q, 2]]]^3, " = ", 
          ExpressionCell[list[[q + 1, 1]]]^3, "+", 
          ExpressionCell[list[[q + 1, 2]]]^3, " = ", 
          ExpressionCell[list[[q, 3]]]}], "Text"]]]], {q, 1, 
     Length[list] - 1}]

Hi Douglas

That might be a solution, however, I never had this problem with V9, it would happily print as soon as it got a solution no matter how many were still to be printed. Its the printing on screen as it encounters a solution is my concern, it just doesn't print anything.

Paul.

Why don't you use Table instead of Reap and Sow?