PROGRAM nearres

c	Looks for residues that are within criterion in one ORTH
c	file for atoms in a reference ORTH file.

	CHARACTER*80	filnam
	CHARACTER*8	res, list(0:999)
	REAL		x(3,400), y(3), dist(999)/999*999./

c	First open input files

	WRITE (6, 1000) 'Enter filename for input ORTH file:'
1000	FORMAT (10a)
	READ (5, 1000) filnam

	OPEN (unit=1, form='FORMATTED', status='OLD', file=filnam,
	1	readonly)

	WRITE (6, 1000) 'Enter filename for input reference ORTH file:'
	READ (5, 1000) filnam

	OPEN (unit=2, form='FORMATTED', status='OLD', file=filnam,
	1	readonly)

c	Get distance criteria

	WRITE (6, 1000) 'Enter distance criteria:'
	READ (5, 1001) crit
1001	FORMAT (3f10.6, 34x, a8)
	crit = crit*crit

c	Read header records

	DO i = 1,3
	  READ (1, 1000)
	  READ (2, 1000)
	endDO

c	Read and store reference coordinates

	DO n = 1,400
	  READ (2, 1001, end=9) (x(i,n), i=1,3)
	endDO
9	num = n-1

c	Loop through file

	nres = 0
	DO WHILE (.TRUE.)
10	  READ (1, 1001, end=19) y, res
	  DO i = 1,num
	    dd = (x(1,i)-y(1))**2 + (x(2,i)-y(2))**2 + (x(3,i)-y(3))**2
	    IF (dd .LE. crit) THEN
	      isit = 0
	      DO n = 1,nres
	        IF (res .EQ. list(n)) THEN
		  isit = n
		  GOTO 11
		endIF
	      endDO
11	      IF (isit .EQ. 0) THEN
	        nres = nres+1
	        list(nres) = res
	        n = nres
	      endIF
	      d1 = (x(1,1)-y(1))**2 + (x(2,1)-y(2))**2 + (x(3,1)-y(3))**2
	      dist(n) = MIN(dist(n),d1)
	    endIF
	  endDO
	endDO

c	Write results

19	CLOSE (unit=1)
	CLOSE (unit=2)

	WRITE (6, 1002) (list(n), SQRT(dist(n)), n=1,nres)
1002	FORMAT (5(2x, a8, f6.2))

	end