more useful GDB_xxx tool functions.

gdbtools.c

@@ -7,14 +7,31 @@
 /* these are for debuging in GDB */
 #include "allvars.h"
 
-int particle_by_id(MyIDType id) {
+int GDB_particle_by_id(MyIDType id, int from) {
     int i;
-    for(i = 0; i < NumPart; i++) {
+    for(i = from; i < NumPart; i++) {
         if(P[i].ID == id) return i;
     }
     return -1;
 }
-char * particle_by_timebin(int bin) {
+
+int GDB_particle_by_type(int type, int from) {
+    int i;
+    for(i = from; i < NumPart; i++) {
+        if(P[i].Type == type) return i;
+    }
+    return -1;
+}
+
+int GDB_particle_by_generation(int gen, int from) {
+    int i;
+    for(i = from; i < NumPart; i++) {
+        if(P[i].Generation == gen) return i;
+    }
+    return -1;
+}
+
+char * GDB_particle_by_timebin(int bin) {
     int i;
     static char buf[1024];
     char tmp[1024];