diff --git a/src/parse/FT_replace_value_in_line.m b/src/parse/FT_replace_value_in_line.m
index 16058922ed7850916da1b7978b60be15d44aa70e..ac72dde78675359c419c4e712a87c18b9f58b01f 100644
--- a/src/parse/FT_replace_value_in_line.m
+++ b/src/parse/FT_replace_value_in_line.m
@@ -46,7 +46,8 @@ function [outstring] = FT_replace_value_in_line(instring, position, value)
   if (isstr(value))
     str2=value;
   else
-    str2=num2str(value);
+    precision = 9+floor(log10(value+1));
+    str2=num2str(value,precision);
   end