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+--- Thread: DIM in a program (/thread-1020.html)
DIM in a program - Angus - 04-02-2014 09:24 AM
imagine this piece of code:
Code:
EXPORT foo()
BEGIN
LOCAL vec=[1,2,3,4,5];
LOCAL dim1:=DIM(vec);
dim1:=dim1(1); //splitting in 2 steps is ok...
LOCAL dim2:=DIM(vec)(1) //while this is not
(...)
END;Is it really not possible to assign something like DIM(vector)(1) to a local in one step?
I tried in cas and that works. I switched home from rpn to textbook and found that calling DIM(vec)(1) is translated to DIM(vec)*(1) there which seems to be a side effect of automatic operator expansion. However in a program such behaviour is painful, you just would not expect your code to be modified by the system.
RE: DIM in a program - eried - 04-02-2014 09:47 AM
Why are you using the return of dim as a list? dim returns the length of the string
RE: DIM in a program - Angus - 04-02-2014 10:03 AM
Maybe that is another capitalized non-capitalzed matter?
In fact I expected the length to be a number and not a list containing the length. I found that I got a list.... But I did use DIM in the program.
A few seconds ago I tried both dim() and DIM() in the cas.
vec:=[1,2,3,4,5];
invocing dim(vec) in the cas turns to DIM(vec) in the history und results in 5.
invocing DIM(vec) in the cas gives {5}.
That is strange
P.S. The original question on splitting up a command to part1*part2 remains, though. For a student learning to program that can really become a problem don't you think?
RE: DIM in a program - eried - 04-02-2014 10:09 AM
Strange, I get 1 with dim and lowercase dim gets uppercased.
Well, yeah I don't like a lot the * thing either, seems counter intuitive but there should be a reason because otherwise why the calculator ask "create ___ variable?" instead of just creating it, it might be related to something internal. I think the double quotes handling (try to use a string function in the cas and modify something later, without undo/redo is even more frustrating) in the cas is much more annoying than the * thing.
RE: DIM in a program - Angus - 04-02-2014 10:46 AM
I forgot to mention that I used the simulator. There dim() is also converted to uppercase and the result is as expected. But using uppercase DIM() from the beginning gives you a list containing the result.
Have to validate that with the calculator later the day.
edit: I checked it in the calculator doing DIM(vec) in the cas causes an "Unmatch control word" error. So the beaviour is different than in my simulator.
But I still get a list from dim used in a program. Could someone please confirm that?
RE: DIM in a program - eried - 04-02-2014 11:48 AM
The lower/upper case explain at least the issue in the code, this works:
Code:
LOCAL dim2:=EXPR("dim("+vec+")(1)");The CAS/Program DIM just returns 1 number, not a list.
RE: DIM in a program - Angus - 04-02-2014 12:12 PM
That is astounding: I just keep getting a list or an Error (from inside a program in cas itself things are fine). Starts getting frustrating.
Thank you anyhow - maybe we get some more comments here and my fault is solved.