--- doc/docbook/src/plplotdoc.texi.orig
+++ doc/docbook/src/plplotdoc.texi
@@ -6722,7 +6722,7 @@
 	if (pm->fdata[i] > max)
 	max = pm->fdata[i];
 
-	sprintf( interp->result, "%f", max );
+	sprintf( Tcl_GetStringResult(interp), "%f", max );
 	return TCL_OK;
 	@}
 
@@ -6735,7 +6735,7 @@
 	if (pm->fdata[i] < min)
 	min = pm->fdata[i];
 
-	sprintf( interp->result, "%f", min );
+	sprintf( Tcl_GetStringResult(interp), "%f", min );
 	return TCL_OK;
 	@}