On the Function problem

*To*: mathgroup at yoda.ncsa.uiuc.edu*Subject*: On the Function problem*From*: "Roger B. Kirchner" <kirchner at cs.umn.edu>*Date*: Wed, 10 Oct 90 11:50:19 CDT

Several people have pointed out that the problem with Function is a bug in Derivative[1] which doesn't know how to handle Subtract in the version of Function which uses variables. The bug seems to be in all current versions of Mathematica. A couple of people have observed that the problem does not exist with the version of Function which uses slots. This is just as good for my purposes because I want to deemphasize variable names in function definitions. In[1]:= f = Function[x, x^2 - x] 2 Out[1]= Function[x, x - x] In[2]:= f'[x] 2 Out[2]= (Function[x, x - x])'[x] In[3]:= g = Function[#^2 - #] 2 Out[3]= #1 - #1 & In[4]:= g'[x] Out[4]= -1 + 2 x Roger Kirchner rkirchne at mathcs.carleton.edu