Add more symmetries, update docs about cell settings

2 files changed, 14 insertions, 1 deletions

diff --git a/src/cell.c b/src/cell.c
index d12191a7..7b5379a5 100644
--- a/src/cell.c
+++ b/src/cell.c
@@ -801,6 +801,7 @@ static void cell_set_pointgroup_from_pdb(UnitCell *cell, const char *sym)
 
 	if ( strcmp(sym, "P 63") == 0 ) new = "6";
 	if ( strcmp(sym, "P 21 21 21") == 0 ) new = "222";
+	if ( strcmp(sym, "P 2 2 2") == 0 ) new = "222";
 	if ( strcmp(sym, "P 43 21 2") == 0 ) new = "422";
 
 	if ( new != NULL ) {
diff --git a/src/symmetry.c b/src/symmetry.c
index 48194c8c..9153049d 100644
--- a/src/symmetry.c
+++ b/src/symmetry.c
@@ -52,8 +52,10 @@ static int check_cond(signed int h, signed int k, signed int l, const char *sym)
 		return ( (((h>0) && (k>=0)) || ((h==0) && (k==0))) && (l>=0)
 		         && (h>=k) );  /* Like 6/mmm */
 	if ( strcmp(sym, "422") == 0 )
-		return ( (((h>=0) && (k>0)) || ((h==0) && (k==0)))
+		return ( (((h>0) && (k>=0)) || ((h==0) && (k==0)))
 		         && (h>=k) );
+	if ( strcmp(sym, "4") == 0 )
+		return ( ((h>0) && (k>=0)) || ((h==0) && (k==0)) );
 
 	/* Hexagonal */
 	if ( strcmp(sym, "6") == 0 )
@@ -89,6 +91,7 @@ int num_general_equivs(const char *sym)
 	if ( strcmp(sym, "mmm") == 0 ) return 8;
 
 	/* Tetragonal */
+	if ( strcmp(sym, "4") == 0 ) return 4;
 	if ( strcmp(sym, "422") == 0 ) return 8;
 	if ( strcmp(sym, "4/mmm") == 0 ) return 16;
 
@@ -145,6 +148,15 @@ void get_general_equiv(signed int h, signed int k, signed int l,
 		}
 	}
 
+	if ( strcmp(sym, "4") == 0 ) {
+		switch ( idx ) {
+		case  0 : *he = h;   *ke = k;   *le = l;  return;
+		case  1 : *he = -h;  *ke = -k;  *le = l;  return;
+		case  2 : *he = -k;  *ke = h;   *le = l;  return;
+		case  3 : *he = k;   *ke = -h;  *le = l;  return;
+		}
+	}
+
 	if ( strcmp(sym, "422") == 0 ) {
 		switch ( idx ) {
 		case  0 : *he = h;   *ke = k;   *le = l;  return;