[Reduce-algebra-developers] Patches to differentiation

[Rainer S. <rai...@gm...>]

If you update your svn working copy, you see a new version of

   packages/poly/diff.red

It contains two improvements to the differentiation routines. The first comes 
from odesolve/odepatch.red, by F.J. Wright, in the ongoing work to fold function 
redefinitions into the main code:

     Differentiation of a parameter-dependent integral must not omit
     differentiation of the upper limit. E.g.

     on allowdfint,dfint;
     depend x,v:
     df(int(f(v,x),x),v);

     should give

     df(xx,vv)*f(vv,xx) + int(df(f(vv,xx),vv),xx)

     Up to now, the first term was missing.

The second change concerns application of the chain rule for interdependent 
nested derivatives, e.g.

     df(df(v,x,y,z),a)

     where v depends on a, when the switch expanddf is on.

Tests and examples can be found in

  packages/regressions/sep-05-2011-expanddf.{tst,rlg}


     Rainer