'Output background coefficients of GSAS f5 in file for plotting
macro Out_GSAS_f5(file)
{
   out file
     Out(bk1, " %11.5f")
     Out(bk2, "\n %11.5f")
     Out(bk3, "\n %11.5f")
     Out(bk4, "\n %11.5f")
     Out(bk5, "\n %11.5f")
     Out(bk6, "\n %11.5f")
     Out(bk7, "\n %11.5f")
     Out(bk8, "\n %11.5f")	    
}