function edge(x)
	common /PAWPAR/ par(5)
	
	x0 = par(1)
	a  = 1.0/par(2)
	s  = par(3)
	c  = par(4)
	b  = par(5)
	y  = -x + x0

	edge = c*exp(a*y)*freq(-y/s-a*s)+b
	
	end