functions in correl.i - f

             compute 4 pt correlation function in 1D  
 
   flag pp = defines the number of pts over which to average   
   EXAMPLE   
   #include "randfield.i"  
   ui=genrandfield1D(20); u=fft(ui,[-1]).re;  
   res =fourptcor1D(u)  
       
interpreted function, defined at contrib/correl.i   line 896