PROGRAM packing

c	Applies translational components to PCD holoenzyme and looks for contacts
c	in adjacent molecules

	PARAMETER	NDIM=44000
	CHARACTER*60	file
	CHARACTER*15	label(NDIM)
	REAL		x(3,NDIM), trans(3,14), dx(3)

	WRITE (6, 1000) 'Enter input filename:'
1000	FORMAT (a)
	READ (5, 1000) file
	OPEN (unit=1, status='OLD', file=file, readonly, form='FORMATTED')

c	Read and store data

	DO i = 1,3
	  READ (1, 1000)
	endDO
	num = 1
	DO WHILE (.TRUE.)
	  READ (1, 1001, end=99) (x(i,num), i=1,3), label(num)
1001	  FORMAT (3f10.4, 34x, a)
	  num = num+1
	endDO

99	CLOSE (unit=1)
	num = num-1
	TYPE *, num

c	Loop through list looking for distances < 4 Ang.  Only need to look at
c	molecules aligned along the crystal axes (6 cases) or by body-centering
c	(8 cases).  First set up array of translations.

	aa = 197.17
	bb = 127.03
	cc = 134.18
	beta = 97.64

	trans(1,1) = aa
	trans(2,1) = 0.
	trans(3,1) = 0.

	trans(1,2) = -aa
	trans(2,2) = 0.
	trans(3,2) = 0.

	trans(1,3) = 0.
	trans(2,3) = bb
	trans(3,3) = 0.

	trans(1,4) = 0.
	trans(2,4) = -bb
	trans(3,4) = 0.

	trans(1,5) = 0.
	trans(2,5) = 0.
	trans(3,5) = cc

	trans(1,6) = 0.
	trans(2,6) = 0.
	trans(3,6) = -cc

	trans(1,7) = aa/2.
	trans(2,7) = bb/2.
	trans(3,7) = cc/2.

	trans(1,8) = -aa/2.
	trans(2,8) = bb/2.
	trans(3,8) = cc/2.

	trans(1,9) = aa/2.
	trans(2,9) = -bb/2.
	trans(3,9) = cc/2.

	trans(1,10) = -aa/2.
	trans(2,10) = -bb/2.
	trans(3,10) = cc/2.

	trans(1,11) = aa/2.
	trans(2,11) = bb/2.
	trans(3,11) = -cc/2.

	trans(1,12) = -aa/2.
	trans(2,12) = bb/2.
	trans(3,12) = -cc/2.

	trans(1,13) = aa/2.
	trans(2,13) = -bb/2.
	trans(3,13) = -cc/2.

	trans(1,14) = -aa/2.
	trans(2,14) = -bb/2.
	trans(3,14) = -cc/2.

c	Loop through checking orthogonal distance

	cb2 = 2.*COSD(beta)

	DO n = 1,num
	  DO m = 1,num
	    DO j = 1,14
	      DO i = 1,3
		dx(i) = x(i,n)-(x(i,m)+trans(i,j))
	      endDO
	      dd = dx(1)**2+dx(2)**2+dx(3)**2+cb2*dx(1)*dx(3)
	      IF (dd .LE. 16.) THEN
	        WRITE (6, 1002) j, label(n), SQRT(dd), label(m)
1002		FORMAT (i3, 2x, a, f8.4, 2x, a)
	      endIF
	    endDO
	  endDO
	endDO

	stop
	end