[LON-CAPA-users] multiple response boxes

Stefan Bisitz lon-capa-users@mail.lon-capa.org
Fri, 03 Oct 2008 22:32:09 +0200

On Friday, October 3, 2008 5:43 pm, Lon Mitchell wrote:
> What are the possible interactions among multiple response boxes in 
> a question?  I have found examples of questions where a custom 
> response boxes are used, and a perl routine compares the separate
> inputs, for example, to check the off-diagonal elements of a
> matrix to see if it is symmetric, but this seems to limit  the
> computer algebra system role in evaluating the result.  In
> particular, is it possible to have non-custom 
> response boxes interact?
> For an example that might justify the above, what about asking 
> "Give a 2x2 symmetric matrix with no zero entries and calculate
> its characteristic polynomial" (perhaps this could be a leading 
> question to a discussion about symmetric matrix eigenvalues).
> We could use custom response boxes to check that the matrix is
> symmetric and has no zero entries using perl, but it would then
> be nice to invoke maxima to find the characteristic polynomial
> and provide it to a standard formula response box to check the
> other student entry.
> Finally, are multiple response boxes the best way to ask for a 
> matrix answer?
> Thanks,
> Lon Mitchell

Hi Lon,

You could use the function &cas() to call maxima within a perl script
block. This allows to access the computer algebra system in custom
response. Please visit the online help for details.

At Wolfenbuettel University we created some of these kind of matrix
problems in the way you described. Yes, multiple response boxes are
useful for this. Peter Riegler and Susanne Bellmer may wish to add more

By the way, is your brother called Capa? ;-)
(I hope you don't take this too seriously...)

Stefan Bisitz