Compose versus Composition
- To: mathgroup at yoda.physics.unc.edu
- Subject: Compose versus Composition
- From: bss at physics.att.com
- Date: Sun, 24 Jan 93 15:19:47 EST
Dear Mathgroup,
Version 1 of MMA had a "Compose" function
which is very convenient for a particular kind of operation.
I need to apply a set of "Heads"
to a set of "variables" in order to form a matrix of functions
(these are natural in quantum calculations of "Slater determinants"),
and under MMA version 1, a simple command produces this matrix. A simple
example is with two functions f and g :
----------------------------------------------------------------
In[35]:= Outer[Compose,{f,g},{x,y}]
Compose::obsfn: Compose is an obsolete function, superseded by Composition.
Out[35]= {{f[x], f[y]}, {g[x], g[y]}}
------------------------------------------------------------
Under MMA version 2 and later I have been unable to figure out
any way of doing this with Composition, Map,...
For the moment I am carrying on, ignoring the ugly error messages,
but would like to know how it is done in version 2.
Any suggestions?
Sriram Shastry
bss at physics.att.com
Jan 24 , 93 Murray Hill