Thank you Stuart! Doug
Douglas Mills Director of Instructional Technologies Department of Chemistry University of Illinois dmi...@illinois.edu (217) 244-5739 On 3/30/15, 1:22 PM, "Stuart Raeburn" <raeb...@msu.edu> wrote: >Hi Doug, > >> I might be mistaken but I *thought* in the past I'd seen Lon-Capa >> recognize different ways of expressing the same value as "you've >> entered that answer before" and not counting the attempt in >> numericalresponse problems. > >Submitting (incorrect) answers of 0.650 and 0.65 for a >numericalresponse item results in tries being charged for both >submissions in LON-CAPA versions 2.9, 2.10, and 2.11. > >Checking if the same answer was submitted for a numericalresponse item >is determined in the end_numericalresponse() routine in >/home/httpd/lib/perl/Apache/caparesponse.pm, which in turn calls the >check_for_previous() routine in /home/httpd/lib/perl/Apache/response.pm > >The check involves a string comparison of the current submission with >each of the previous submissions made by the student for the same >instance of the response item. > >If there is an exact match between the value of the current submission >and the value of a past submission, (and the awards also matched), >then the message: 'You have entered that answer before' will be shown >and no try will be charged. >(Exception: survey items, or items where the random seed has changed, >i.e., randomizetry parameter in effect). > >That string comparison part of the implementation has not changed from >response.pm rev. 1.32 (8/3/2001) and caparesponse.pm rev. 1.38 >(8/3/2001). > > >Stuart Raeburn >LON-CAPA Academic Consortium > >Quoting "Mills, Douglas G" <dmi...@illinois.edu>: > >> Hi All, >> >> I might be mistaken but I *thought* in the past I'd seen Lon-Capa >> recognize different ways of expressing the same value as "you've >> entered that answer before" and not counting the attempt in >> numericalresponse problems. Am I wrong about that? I thought >> entries such as .650 and 0.650 were recognized as the same answer >> and the second entry then not counted as a try where there a limited >> number of tries, but if that had been the case in the past, it does >> not seem to be the case now. A student reported using her two >> tries on a test retake with just those two answers (why, I don't >> know!) and my subsequent testing of that and some other items >> confirmed that attempts are not counted by values but by different >> expressions of those values -- as if the problem were a >> stringresponse. That was not what I expected. Thank you for any >> further guidance on that. Could it be related to changes addressing >> differences between decimals with trailing zeros (so .650 is not >> the same as .65 for purposes of sig figs) or something? Or was I >> imagining that those different expressions were recognized as the >> same value in the past? >> >> Doug >> >> Douglas Mills >> Director of Instructional Technologies >> Department of Chemistry >> University of Illinois >> dmi...@illinois.edu<mailto:dmi...@illinois.edu> >> (217) 244-5739 > >_______________________________________________ >LON-CAPA-users mailing list >LON-CAPA-users@mail.lon-capa.org >http://mail.lon-capa.org/mailman/listinfo/lon-capa-users _______________________________________________ LON-CAPA-users mailing list LON-CAPA-users@mail.lon-capa.org http://mail.lon-capa.org/mailman/listinfo/lon-capa-users
