
Using user-written models, statistics, and methods in Sherpa
------------------------------------------------------------

It is possible to extend Sherpa by adding user-defined models,
statistics, and optimization methods. 

 - README.model describes how to write and use user-defined models

 - README.stat describes how to write your own statistic

 - README.method describes how to write your own optimization method

A note for Intel/Mac users
--------------------------

The CIAO 3.4.1.1 build uses the PPC emulation capabilities of OS-X -
as described at http://www.apple.com/rosetta/ - to run on Intel Mac
machines. This means that compiled user models have to be built as
PowerPC libraries to be able to be used by Sherpa. The OS-X Makefiles
have been updated to support this by adding

  -arch ppc

to both the compile and link lines.

