DPR fortranization 

There is  MakeA.r ratfor file which is converted to fortran by invoking the command 

To reproduce this from the ratfor obviously requires some version of ratfor
which is discussed here:  http://www.econ.uiuc.edu/~roger/repro.html

Since the MakeA.f is provided here you don't actually need to worry about ratfor at all.

Then source("dpr.R")  gives a scatter plot that illustrates that the R version
of the loop and the fortran version are consistent, but the fortran version is
roughly 60 times faster.  
