PROGRAM corelb

c	Calculate correlation coefficient of B's with distance from origin

	REAL*8	s1, s2
	REAL	rad(10000), bb(10000)

c	First read information

	OPEN (unit=1, file='pcd.pdb.A', form='FORMATTED', status='OLD',
	1	readonly)

	n = 1
	DO WHILE (.TRUE.)
	  READ (1, 1001, end=9) x, y, z, b
1001	  FORMAT (30x, 3f8.3, 6x, f6.2)
	  n = n + 1
	  rad(n) = SQRT(x*x+y*y+z*z)
	  bb(n) = b
	endDO

9	CLOSE (unit=1)

c	Adjust means to zero

	s1 = 0.0d0
	s2 = 0.0d0
	DO i = 1,n
	  s1 = s1 + rad(i)
	  s2 = s2 + bb(i)
	endDO
	rm = s1/n
	bm = s2/n
	DO i = 1,n
	  rad(i) = rad(i) - rm
	  bb(i) = bb(i) - bm
	endDO

c	Calculate result

	s1 = 0.0d0
	s2 = 0.0d0
	s12 = 0.0d0
	DO i = 1,n
	  s1 = s1 + rad(i)**2
	  s2 = s2 + bb(i)**2
	  s12 = s12 + rad(i)*bb(i)
	endDO

	corr = s12/SQRT(s1*s2)

	WRITE (6, 1002) corr
1002	FORMAT (f10.4)

	end