1 files changed, 9 insertions, 0 deletions
diff --git a/tksao/frame/wcsast.C b/tksao/frame/wcsast.C
index de5c3a6..18d930b 100644
--- a/tksao/frame/wcsast.C
+++ b/tksao/frame/wcsast.C
@@ -56,6 +56,15 @@ int wcsSkyFrame(AstFrameSet* ast, Coord::SkyFrame sky)
 
 void wcsFormat(AstFrameSet* ast, int id, const char* format)
 {
+  // is it already set?
+  // ast is very slow when changing params
+  {
+    ostringstream str;
+    str << "Format(" << id << ")" << ends;
+    const char* out = astGetC(ast, str.str().c_str());
+    if (!strcmp(out,format))
+      return;
+  }
   ostringstream str;
   str << "Format(" << id << ")=" << format << ends;
   astSet(ast, str.str().c_str());