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Full Version: ΣLIST, ΠLIST and ΔLIST with vectors [SOLVED]
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Are these three functions intended to work also with vectors?

I've found that they have the following behavior, using firmware (8151):
  • ΣLIST works well with lists and with vectors
  • ΠLIST does not work with vectors. The HP Prime freezes, and restarts after a few seconds; the Windows emulator issues the error "The application has crashed and will be restarted"
  • ΔLIST does not work with vectors. Both the HP Prime and the Windows emulator show a message error on the screen (white cross on a red circle), when in RPN mode, and "Error: bad argument type" when in textbook mode
Do you have examples that don't work?

These vectors seem to work ok:
M1:=[1 2 3 4];
M2:=2*M1;

ΣLIST({M1,M2}); ==> [3,6,9,12]
ΠLIST({M1,transpose(M2)}); ==> [60]
ΔLIST({M1,M2}); ==> {[1 2 3 4]}
ΣLIST(M1); ==> 10
ΠLIST(M1); ==> restart
but:
ΠLIST(mat2list(M1)); ==> 24
In my case, the direct use of a vector produces the error:

ΠLIST([1 2 3]) ==> restart
ΔLIST ([1 2 3]) ==> error
(01-30-2016 01:17 PM)Didier Lachieze Wrote: [ -> ]ΠLIST(M1); ==> restart

Well, that's not very graceful, is it? To be fair, the help description does specify a list as the argument. Also, the function, "calculates the product of all elements in a list," and since there is no list, there are no elements to calculate, but one could surely imagine better ways to exit than simply, crashing...
I agree with DrR, but the help description for ΣLIST says: "calculates the sum of all elements in a list", and the function also works for vectors.

ΣLIST({1 2 3}) ==> 6
ΣLIST([1 2 3]) ==> 6
I think I read somewhere that the treatment of vectors and lists is generally the same. So ΣLIST([1 2 3]); should be the same as ΣLIST(mat2list([1 2 3])); and by extension, so should ΠLIST([1 2 3]) be the same as ΠLIST(mat2list([1 2 3])); so this seems like a valid bug and I know the team is aware of it.

-Dale-
Is on the list. Thanks!
Corrected in firmware 10077.

Thanks to the HP Prime Team!
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