How to put decimal in the substring function

Hi Friends

I am having a input value which is a UDF named GetValue which is mapped with a substring (0,4) which is again mapped to a split by value and then to the target field MENGE

My problem is when value is coming from GetValue and i am mapping it to substring there i want to take the decimals also

forexample let us value coming is 2 than in the substring and then to the target field i want to send as 2.000.

Please help me how it can be done.

Thanks