[system] Repository:
ViewVC logotype

Revision 3314

Jump to revision: Previous Next
Author: gage
Date: Fri Jun 24 20:11:23 2005 UTC (14 years, 4 months ago)
Log Message:
Fixed conceptual error in compare_vec_solution.  This should fix bug
#670.  In my opinion the entire concept of vec_solution_cmp should be
reconsidered.  In solving an underdetermined linear equation of the form
Ax-b=0 it seems to me that the solutions answer in the form:
x= a +bt+cu+ds  where a,b,c,d are vectors should simply be evaluated
to see if it satisfies Ax-b=0 for 5 or six values of a,b,c,d  --
checking the solution should use a
vector valued version of fun_cmp.

As it is, the student's coefficients for a,b,c,d are compared with the
instructors to see if they span the same space. This is quite a bit more
complicated -- and indeed the method came up with the wrong answer.

I believe I have the method corrected, but I would suggest that this
answer evaluator be replaced with one which operates more
directly and is therefore easier to maintain.  Am I missing something in
this analysis?  Has someone else created answer evaluators for this type
of problem?

 -- Mike

Changed paths:

Path Details
Directorytrunk/pg/macros/PGmorematrixmacros.pl modified , text changed

aubreyja at gmail dot com
ViewVC Help
Powered by ViewVC 1.0.9