30
31
32
33#include "implicit_f.inc"
34
35
36
38 . x1, x2, x3, x4, y1, y2, y3, y4,
39 . z1, z2, z3, z4,amax,fac
40
41
42
43 INTEGER IDE,
45 . x12,y12,z12,x23,y23,z23,x34,y34,z34,x41,y41,z41,a,
46 . rx,ry,rz,sx,sy,sz,nx,ny,nz
47
48 rx = x2+x3-x1-x4
49 ry = y2+y3-y1-y4
50 rz = z2+z3-z1-z4
51 sx = x3+x4-x1-x2
52 sy = y3+y4-y1-y2
53 sz = z3+z4-z1-z2
54 nx = ry * sz - rz * sy
55 ny = rz * sx - rx * sz
56 nz = rx * sy - ry * sx
57
58 a = nx*nx+ny*ny+nz*nz
59 ide = 0
60 x12 = x2 - x1
61 y12 = y2 - y1
62 z12 = z2 - z1
63 IF (x12==zero.AND.y12==zero.AND.z12==zero) THEN
64 ide = 1
65 GOTO 10
66 ENDIF
67
68 x23 = x2 - x3
69 y23 = y2 - y3
70 z23 = z2 - z3
71 IF (x23==zero.AND.y23==zero.AND.z23==zero) THEN
72 ide = 1
73 GOTO 10
74 ENDIF
75
76 x34 = x4 - x3
77 y34 = y4 - y3
78 z34 = z4 - z3
79 IF (x34==zero.AND.y34==zero.AND.z34==zero) THEN
80 ide = 1
81 GOTO 10
82 ENDIF
83
84 x41 = x4 - x1
85 y41 = y4 - y1
86 z41 = z4 - z1
87 IF (x41==zero.AND.y41==zero.AND.z41==zero) THEN
88 ide = 1
89 GOTO 10
90 ENDIF
91
92 10 CONTINUE
93
94 IF (a > amax )THEN
95 it=ide
96 amax = a
97 END IF
98 RETURN