Hi, I don't think that it is helpful to give hints for syntactically correct but semantically incorrect submissions: How can one know what the student means? Students have to learn to produce valid expressions. One could write simple problems for that purpose and a short manual.
In my option using customresponse is the appropriate method. You can find an example (source available) how to check your mentioned most common syntax problems in 'scl/dencker/testing/examples/simple syntax check 1.problem' This example is a (hopefully correct) reduction of a more ambitious library. The library has to be rewritten and is not finished yet - to put it mildly. I will keep you informed ... - Peter Am 21.10.2013 16:23, schrieb Angus Findlay: > When I give students formula response questions some of them don’t submit > valid mathematic expressions. The most common problems are: > > 1) Not having balanced brackets. (i.e. number of left brackets do not match > number of right brackets) > 2) Including invalid characters, such as quotation signs. > 3) Not including brackets, when necessary. (eg. 2^-1/2 instead of 2^(-1/2)) > > I want to tell them that the expression is invalid, tell them why, and allow > them to enter it again, without penalty. (Right now my LON-CAPA server times > out on them, and asks them to try again later.) > > Is there a piece of standard code I can use for this, or if not, what it the > easiest to implement a solution to this? > > Thanks in advance. > > Respectfully, > ---------------------------------------------- > Mr. Angus Findlay > Math Department, Mount Allison University > Sackville, New Brunswick > > email: afind...@mta.ca tel: 506-364-2592 > ---------------------------------------------- > > > > > _______________________________________________ > LON-CAPA-users mailing list > LON-CAPA-users@mail.lon-capa.org > http://mail.lon-capa.org/mailman/listinfo/lon-capa-users > -- Dr. Peter Dencker wissenschaftl. Mitarbeiter UNIVERSITÄT ZU LÜBECK INSTITUT FÜR MATHEMATIK Ratzeburger Allee 160 23562 Lübeck Tel +49 451 500 4254 Fax +49 451 500 3373 denc...@math.uni-luebeck.de www.math.uni-luebeck.de _______________________________________________ LON-CAPA-users mailing list LON-CAPA-users@mail.lon-capa.org http://mail.lon-capa.org/mailman/listinfo/lon-capa-users
