aboutsummaryrefslogtreecommitdiff
path: root/src/symmetry.c
blob: 6f3ce675a704c0578a6e87b18f6b0fd597d2f970 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
/*
 * symmetry.c
 *
 * Symmetry
 *
 * (c) 2006-2010 Thomas White <taw@physics.org>
 *
 * Part of CrystFEL - crystallography with a FEL
 *
 */


#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdlib.h>
#include <stdio.h>
#include <math.h>

#include "utils.h"


#ifdef DEBUG
#define SYM_DEBUG STATUS
#else /* DEBUG */
#define SYM_DEBUG(...)
#endif /* DEBUG */


/* Check if a reflection is in the asymmetric unit cell */
static int check_cond(signed int h, signed int k, signed int l, const char *sym)
{
	if ( strcmp(sym, "1") == 0 )
		return ( 1 );
	if ( strcmp(sym, "-1") == 0 )
		return ( 1 );
	if ( strcmp(sym, "6") == 0 )
		return ( ((h>0) && (k>=0)) || ((h==0) && (k==0)) );
	if ( strcmp(sym, "6/m") == 0 )
		return ( (((h>0) && (k>=0)) || ((h==0) && (k==0))) && (l>=0) );
	if ( strcmp(sym, "6/mmm") == 0 )
		return ( (((h>0) && (k>=0)) || ((h==0) && (k==0))) && (l>=0)
		         && (h>=k) );

	/* TODO: Add more groups here */

	return 1;
}


/* Macros for checking the above conditions and returning if satisfied */
#define CHECK_COND(h, k, l, sym)                   \
	if ( check_cond((h), (k), (l), (sym)) ) {  \
		*hp = (h);  *kp = (k);  *lp = (l); \
		return;                            \
	}


int num_equivs(signed int h, signed int k, signed int l, const char *sym)
{
	/* 000 is always unique */
	if ( (h==0) && (k==0) && (l==0) ) return 1;

	if ( strcmp(sym, "1") == 0 ) return 1;

	if ( strcmp(sym, "-1") == 0 ) return 2;

	if ( strcmp(sym, "6") == 0 ) {
		if ( (h==0) && (k==0) ) return 1;  /* a */
		return 6;  /* b */
	}

	if ( strcmp(sym, "6/m") == 0 ) {
		if ( (h==0) && (k==0) ) return 2;  /* a */
		if ( l == 0 ) return 6;  /* b */
		return 12;  /* c */
	}

	if ( strcmp(sym, "6/mmm") == 0 ) {
		if ( (h==0) && (k==0) ) return 2;  /* a */
		if ( (l==0) && (h==k) ) return 6;  /* b */
		if ( (l==0) && (k==0) ) return 6;  /* c */
		if ( h == k ) return 12;  /* d */
		if ( k == 0 ) return 12;  /* e */
		if ( l == 0 ) return 12;  /* f */
		return 24;  /* g */
	}

	/* TODO: Add more groups here */

	return 1;
}


void get_equiv(signed int h, signed int k, signed int l,
               signed int *he, signed int *ke, signed int *le,
               const char *sym, int idx)
{
	signed int i = -h-k;

	if ( strcmp(sym, "1") == 0 ) {
		*he = h;   *ke = k;   *le = l;  return;
	}

	if ( strcmp(sym, "-1") == 0 ) {
		switch ( idx ) {
		case 0 : *he = h;   *ke = k;   *le = l;   return;
		case 1 : *he = -h;  *ke = -k;  *le = -l;  return;
		}
	}

	if ( strcmp(sym, "6") == 0 ) {
		/* a */
		if ( (h==0) && (k==0) ) {
			switch ( idx ) {
			case  0 : *he = 0;   *ke = 0;   *le = l;   return;
			}
		}
		/* b */
		switch ( idx ) {
		case  0 : *he = h;   *ke = k;   *le = l;  return;
		case  1 : *he = i;   *ke = h;   *le = l;  return;
		case  2 : *he = k;   *ke = i;   *le = l;  return;
		case  3 : *he = -h;  *ke = -k;  *le = l;  return;
		case  4 : *he = -i;  *ke = -h;  *le = l;  return;
		case  5 : *he = -k;  *ke = -i;  *le = l;  return;
		}
	}

	if ( strcmp(sym, "6/m") == 0 ) {
		/* a */
		if ( (h==0) && (k==0) ) {
			switch ( idx ) {
			case  0 : *he = 0;   *ke = 0;   *le = l;   return;
			case  1 : *he = 0;   *ke = 0;   *le = -l;  return;
			}
		}
		/* b-c */
		switch ( idx ) {
		case  0 : *he = h;   *ke = k;   *le = l;   return;
		case  1 : *he = i;   *ke = h;   *le = l;   return;
		case  2 : *he = k;   *ke = i;   *le = l;   return;
		case  3 : *he = -h;  *ke = -k;  *le = l;   return;
		case  4 : *he = -i;  *ke = -h;  *le = l;   return;
		case  5 : *he = -k;  *ke = -i;  *le = l;   return;
		case  6 : *he = h;   *ke = k;   *le = -l;  return;
		case  7 : *he = i;   *ke = h;   *le = -l;  return;
		case  8 : *he = k;   *ke = i;   *le = -l;  return;
		case  9 : *he = -h;  *ke = -k;  *le = -l;  return;
		case 10 : *he = -i;  *ke = -h;  *le = -l;  return;
		case 11 : *he = -k;  *ke = -i;  *le = -l;  return;
		}
	}

	if ( strcmp(sym, "6/mmm") == 0 ) {
		/* a */
		if ( (h==0) && (k==0) ) {
			switch ( idx ) {
			case  0 : *he = 0;   *ke = 0;   *le = l;   return;
			case  1 : *he = 0;   *ke = 0;   *le = -l;  return;
			}
		}
		/* b-g */
		switch ( idx ) {
		case  0 : *he = h;   *ke = k;   *le = l;   return;
		case  1 : *he = i;   *ke = h;   *le = l;   return;
		case  2 : *he = k;   *ke = i;   *le = l;   return;
		case  3 : *he = -h;  *ke = -k;  *le = l;   return;
		case  4 : *he = -i;  *ke = -h;  *le = l;   return;
		case  5 : *he = -k;  *ke = -i;  *le = l;   return;
		case  6 : *he = k;   *ke = h;   *le = -l;  return;
		case  7 : *he = h;   *ke = i;   *le = -l;  return;
		case  8 : *he = i;   *ke = k;   *le = -l;  return;
		case  9 : *he = -k;  *ke = -h;  *le = -l;  return;
		case 10 : *he = -h;  *ke = -i;  *le = -l;  return;
		case 11 : *he = -i;  *ke = -k;  *le = -l;  return;
		case 12 : *he = -h;  *ke = -k;  *le = -l;  return;
		case 13 : *he = -i;  *ke = -h;  *le = -l;  return;
		case 14 : *he = -k;  *ke = -i;  *le = -l;  return;
		case 15 : *he = h;   *ke = k;   *le = -l;  return;
		case 16 : *he = i;   *ke = h;   *le = -l;  return;
		case 17 : *he = k;   *ke = i;   *le = -l;  return;
		case 18 : *he = -k;  *ke = -h;  *le = l;   return;
		case 19 : *he = -h;  *ke = -i;  *le = l;   return;
		case 20 : *he = -i;  *ke = -k;  *le = l;   return;
		case 21 : *he = k;   *ke = h;   *le = l;   return;
		case 22 : *he = h;   *ke = i;   *le = l;   return;
		case 23 : *he = i;   *ke = k;   *le = l;   return;
		}
	}

	/* TODO: Add more groups here */

	ERROR("Unrecognised symmetry '%s'\n", sym);
	abort();
}


void get_asymm(signed int h, signed int k, signed int l,
               signed int *hp, signed int *kp, signed int *lp,
               const char *sym)
{
	int nequiv = num_equivs(h, k, l, sym);
	int p;

	SYM_DEBUG("------ %i %i %i\n", h, k, l);
	for ( p=0; p<nequiv; p++ ) {
		signed int he, ke, le;
		get_equiv(h, k, l, &he, &ke, &le, sym, p);
		SYM_DEBUG("%i : %i %i %i\n", p, he, ke, le);
		CHECK_COND(he, ke, le, sym);
	}

	/* Should never reach here */
	ERROR("No match found in %s for %i %i %i\n", sym, h, k, l);
	abort();
}