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-rw-r--r--doc/twin-calculator.odtbin19816 -> 20883 bytes
-rw-r--r--doc/twin-calculator.pdfbin47007 -> 48187 bytes
-rw-r--r--src/symmetry.c70
-rw-r--r--src/symmetry.h4
-rw-r--r--tests/symmetry_check.c168
5 files changed, 222 insertions, 20 deletions
diff --git a/doc/twin-calculator.odt b/doc/twin-calculator.odt
index 56282572..3feba7fe 100644
--- a/doc/twin-calculator.odt
+++ b/doc/twin-calculator.odt
Binary files differ
diff --git a/doc/twin-calculator.pdf b/doc/twin-calculator.pdf
index d1bfc9fd..6d3dd582 100644
--- a/doc/twin-calculator.pdf
+++ b/doc/twin-calculator.pdf
Binary files differ
diff --git a/src/symmetry.c b/src/symmetry.c
index e9c7d642..10c41ba7 100644
--- a/src/symmetry.c
+++ b/src/symmetry.c
@@ -456,7 +456,7 @@ static SymOpList *make_4mm()
SymOpList *new = new_symoplist();
add_symop(new, v(0,-1,0,0), v(1,0,0,0), v(0,0,0,1), 4); /* 4 // l */
add_symop(new, v(-1,0,0,0), v(0,1,0,0), v(0,0,0,1), 2); /* m -| l */
- new->name = strdup("4mmm");
+ new->name = strdup("4mm");
return expand_ops(new);
}
@@ -843,7 +843,7 @@ SymOpList *get_pointgroup(const char *sym)
if ( strcmp(sym, "23") == 0 ) return make_23();
if ( strcmp(sym, "m-3") == 0 ) return make_m3bar();
if ( strcmp(sym, "432") == 0 ) return make_432();
- if ( strcmp(sym, "-432") == 0 ) return make_4bar3m();
+ if ( strcmp(sym, "-43m") == 0 ) return make_4bar3m();
if ( strcmp(sym, "m-3m") == 0 ) return make_m3barm();
ERROR("Unknown point group '%s'\n", sym);
@@ -1057,6 +1057,13 @@ static int ops_equal(const struct sym_op *op,
}
+static int struct_ops_equal(const struct sym_op *op1, const struct sym_op *op2)
+{
+ return ops_equal(op1, op2->h, op2->k, op2->l);
+}
+
+
+
/* Return true if a*b = ans */
static int check_mult(const struct sym_op *ans,
const struct sym_op *a, const struct sym_op *b)
@@ -1079,6 +1086,39 @@ static int check_mult(const struct sym_op *ans,
}
+/* Check that every operation in "target" is also in "source" */
+int is_subgroup(const SymOpList *source, const SymOpList *target)
+{
+ int n_src, n_tgt;
+ int i;
+
+ n_src = num_ops(source);
+ n_tgt = num_ops(target);
+
+ for ( i=0; i<n_tgt; i++ ) {
+
+ int j;
+ int found = 0;
+
+ for ( j=0; j<n_src; j++ ) {
+
+ if ( struct_ops_equal(&target->ops[i],
+ &source->ops[j] ) )
+ {
+ found = 1;
+ break;
+ }
+
+ }
+
+ if ( !found ) return 0;
+
+ }
+
+ return 1;
+}
+
+
/**
* get_ambiguities:
* @source: The "source" symmetry, a %SymOpList
@@ -1100,10 +1140,23 @@ SymOpList *get_ambiguities(const SymOpList *source, const SymOpList *target)
SymOpList *src_reordered;
SymOpMask *used;
char *name;
+ int index;
n_src = num_ops(source);
n_tgt = num_ops(target);
+ if ( !is_subgroup(source, target) ) {
+ ERROR("'%s' is not a subgroup of '%s'\n",
+ symmetry_name(target), symmetry_name(source));
+ return NULL;
+ }
+
+ if ( n_src % n_tgt != 0 ) {
+ ERROR("Subgroup index would be fractional.\n");
+ return NULL;
+ }
+ index = n_src / n_tgt;
+
src_reordered = new_symoplist();
used = new_symopmask(source);
@@ -1205,6 +1258,15 @@ SymOpList *get_ambiguities(const SymOpList *source, const SymOpList *target)
twins = new_symoplist();
for ( i=0; i<n_src; i++ ) {
if ( used->mask[i] == 0 ) continue;
+ if ( determinant(&src_reordered->ops[i]) < 0 ) {
+ /* A mirror or inversion turned up in the list.
+ * That means that no pure rotational ambiguity can
+ * account for this subgroup relationship. */
+ free_symoplist(twins);
+ free_symopmask(used);
+ free_symoplist(src_reordered);
+ return NULL;
+ }
add_copied_op(twins, &src_reordered->ops[i]);
}
@@ -1309,13 +1371,13 @@ void describe_symmetry(const SymOpList *s)
n = num_equivs(s, NULL);
- STATUS("%10s :", symmetry_name(s));
+ STATUS("%15s :", symmetry_name(s));
for ( i=0; i<n; i++ ) {
char *name = name_equiv(&s->ops[i]);
STATUS(" %6s", name);
free(name);
- if ( (i!=0) && (i%8==0) ) STATUS("\n%10s ", "");
+ if ( (i!=0) && (i%8==0) ) STATUS("\n%15s ", "");
}
STATUS("\n");
}
diff --git a/src/symmetry.h b/src/symmetry.h
index 7ad93ece..c91864bb 100644
--- a/src/symmetry.h
+++ b/src/symmetry.h
@@ -47,7 +47,9 @@ extern void get_equiv(const SymOpList *ops, const SymOpMask *m, int idx,
signed int h, signed int k, signed int l,
signed int *he, signed int *ke, signed int *le);
-extern SymOpList *get_ambiguities(const SymOpList *source, const SymOpList *target);
+extern SymOpList *get_ambiguities(const SymOpList *source,
+ const SymOpList *target);
+extern int is_subgroup(const SymOpList *source, const SymOpList *target);
extern int is_centrosymmetric(const SymOpList *s);
extern const char *symmetry_name(const SymOpList *ops);
diff --git a/tests/symmetry_check.c b/tests/symmetry_check.c
index a83b0d53..2e47bf83 100644
--- a/tests/symmetry_check.c
+++ b/tests/symmetry_check.c
@@ -17,11 +17,72 @@
#include <stdlib.h>
#include <stdio.h>
+#include <stdarg.h>
#include "../src/symmetry.h"
#include "../src/utils.h"
+static void find_all_ambiguities(const char *first, ...)
+{
+ va_list vp;
+ int i;
+ const char *arg;
+ SymOpList *test[32];
+ int n = 0;
+
+ test[n++] = get_pointgroup(first);
+
+ va_start(vp, first);
+
+
+ do {
+
+ arg = va_arg(vp, const char *);
+ if ( arg != NULL ) {
+ test[n++] = get_pointgroup(arg);
+ }
+
+ } while ( arg != NULL );
+
+ for ( i=0; i<n; i++ ) {
+
+ SymOpList *holo;
+ int j;
+
+ holo = test[i];
+ STATUS("%7s :", symmetry_name(holo));
+ for ( j=0; j<n; j++ ) {
+
+ SymOpList *twins;
+
+ if ( i == j ) continue;
+
+ if ( !is_subgroup(holo, test[j]) ) continue;
+
+ twins = get_ambiguities(holo, test[j]);
+ if ( twins == NULL ) continue;
+
+ if ( num_equivs(twins, NULL) == 1 ) {
+ free_symoplist(twins);
+ continue;
+ }
+
+ if ( num_equivs(twins, NULL) == 2 ) {
+ STATUS(" %5s ", symmetry_name(test[j]));
+ } else {
+ STATUS(" %5s*", symmetry_name(test[j]));
+ }
+
+ }
+ STATUS("\n");
+
+ }
+
+ STATUS("\n");
+}
+
+
static const char *maybenot(int v)
{
if ( v ) {
@@ -66,11 +127,12 @@ static void check_pg_props(const char *pg, int answer, int centro, int *fail)
static void check_subgroup(const char *ssource, const char *starget,
- int *fail)
+ int should_be_subgroup, int should_be_ambiguity,
+ int n_exp, int *fail)
{
SymOpList *source;
SymOpList *target;
- SymOpList *twins;
+ int sub;
source = get_pointgroup(ssource);
target = get_pointgroup(starget);
@@ -79,8 +141,56 @@ static void check_subgroup(const char *ssource, const char *starget,
return;
}
- twins = get_ambiguities(source, target);
- describe_symmetry(twins);
+ sub = is_subgroup(source, target);
+ if ( sub != should_be_subgroup ) {
+ ERROR("'%s' should%s be a subgroup of '%s', but is%s.\n",
+ starget, maybenot(should_be_subgroup),
+ ssource, maybenot(sub));
+ *fail = 1;
+ return;
+ }
+
+ if ( should_be_subgroup ) {
+
+ SymOpList *twins;
+ int nf;
+ int amb = 1;
+
+ twins = get_ambiguities(source, target);
+ if ( twins == NULL ) amb = 0;
+ if ( amb != should_be_ambiguity ) {
+ ERROR("'%s' should%s be a rotational subgroup of '%s'"
+ " but is%s.\n",
+ starget, maybenot(should_be_ambiguity),
+ ssource, maybenot(amb));
+ *fail = 1;
+ return;
+ }
+
+ if ( amb ) {
+
+ describe_symmetry(twins);
+ nf = num_equivs(twins, NULL);
+ if ( nf != n_exp ) {
+ ERROR("Expected %i operations, found %i\n",
+ n_exp, nf);
+ *fail = 1;
+ return;
+ }
+
+ } else {
+
+ STATUS("%15s : subgroup of %s, but no ambiguity without"
+ " inversion or mirroring\n", starget, ssource);
+
+
+ }
+
+ } else {
+
+ STATUS("%15s : not a subgroup of %s\n", starget, ssource);
+
+ }
free_symoplist(target);
free_symoplist(source);
@@ -145,20 +255,48 @@ int main(int argc, char *argv[])
check_pg_props( "23", 12, 0, &fail);
check_pg_props( "m-3", 24, 1, &fail);
check_pg_props( "432", 24, 0, &fail);
- check_pg_props( "-432", 24, 0, &fail);
+ check_pg_props( "-43m", 24, 0, &fail);
check_pg_props( "m-3m", 48, 1, &fail);
STATUS("\n");
- check_subgroup("2/m", "m", &fail);
- check_subgroup("mmm", "mm2", &fail);
- check_subgroup("-4m2", "-4", &fail);
- check_subgroup("-42m", "-4", &fail);
- check_subgroup("-3m1_H", "-3_H", &fail);
- check_subgroup("-31m_H", "-3_H", &fail);
- check_subgroup("6/mmm", "-3_H", &fail);
- check_subgroup("-432", "m-3m", &fail);
- check_subgroup("m-3", "m-3m", &fail);
- check_subgroup("23", "432", &fail);
+ /* Check some easy subgroups */
+ check_subgroup("2/m", "m", 1, 1, 2, &fail);
+ check_subgroup("mmm", "mm2", 1, 1, 2, &fail);
+ check_subgroup("-4m2", "-4", 1, 1, 2, &fail);
+ check_subgroup("-42m", "-4", 1, 1, 2, &fail);
+ check_subgroup("-3m1_H", "-3_H", 1, 1, 2, &fail);
+ check_subgroup("-31m_H", "-3_H", 1, 1, 2, &fail);
+ check_subgroup("m-3m", "-43m", 1, 1, 2, &fail);
+ check_subgroup("m-3m", "m-3", 1, 1, 2, &fail);
+ check_subgroup("432", "23", 1, 1, 2, &fail);
+ check_subgroup("6/m", "-3_H", 1, 1, 2, &fail);
+ check_subgroup("4/m", "-4", 1, 1, 2, &fail);
+
+ /* Tetartohedral */
+ check_subgroup("6/mmm", "-3_H", 1, 1, 4, &fail);
+
+ /* Check some things that are valid subgroups, but no valid ambiguities
+ * exist because inversions and mirrors are not allowed */
+ check_subgroup("-1", "1", 1, 0, -1, &fail);
+ check_subgroup("4/mmm", "4", 1, 0, -1, &fail);
+ check_subgroup("m-3m", "23", 1, 0, -1, &fail);
+
+ /* Check some invalid combinations */
+ check_subgroup("432", "-43m", 0, 0, -1, &fail);
+ check_subgroup("432", "m-3", 0, 0, -1, &fail);
+
+ /* Derive all merohedral ambiguities */
+ STATUS("\nMerohedral ambiguities:\n\n");
+ find_all_ambiguities("1", "-1", NULL);
+ find_all_ambiguities("2", "m", "2/m", NULL);
+ find_all_ambiguities("mm2", "mmm", "222", NULL);
+ find_all_ambiguities("4", "-4", "-42m", "-4m2", "4mm",
+ "4/m", "422", "4/mmm", NULL);
+ find_all_ambiguities("3_R", "32_R", "-3_R", "3m_R", "-3m_R", NULL);
+ find_all_ambiguities("6", "3_H", "312_H", "321_H", "622", "-3_H",
+ "3m1_H", "-6", "31m_H", "-3m1_H", "-6m2",
+ "-62m", "-31m_H", "6/mmm", "6/m", "6mm", NULL);
+ find_all_ambiguities("23", "432", "-43m", "m-3", "m-3m", NULL);
return fail;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-30 10:09:46 +0000