Replacement of the Imround Macro With a User Function

  I made some minor changes imround macro and it is now a user function that gives the same results.

 It works with Excel's drag and fill method and the Undo button now works.

I started working with a macro since it provided some code that gave an idea of what could be done in Excel. I was interested in the extent to which one could modify a macro at the time. It is easier to pass variables in a function.