Hi All, 

I have written a macro that uses a list of variables, ending in the letters of the alphabet (A, B, C etc.).

It removes the last letter of the variable name and concatenates the remaining substring with _1 (if the last letter was A), _2 (if the last letter was "B") etc and renames the original variable to the new concatenated string. 

However, I need a condition: if the last letter of the variable name is "A", I have to start the count again.

All in all this is what I try to do:

trackA-->track_1

...

trackI-->track_9

trace1-->trace_1

...

traceD-->trace_4

And this is my solution that does not work:

define !rename4 (vlist = !charend('/'))
!let !count = 1
!let !incr = 1
!let !subtr=-1
!do !vname !in (!vlist)   
    !let !len=!length(!vname)
    !let !lastbutonecharacter = !length(!concat(!blank(!len), !blank(!subtr))) 
    !let !lastletter= !last(!vname) 
    !if (!lastletter = 'A') !then 
    !let !count=1  
    !ifend
    !let !newname0 = !substr(!vname, 1, !lastbutonecharacter) 
    !let !newname1 = !concat(!newname0,"_")
    !let !newname = !concat(!newname1, !count)
    rename variables (!vname = !newname).
    !let !count = !length(!concat(!blank(!count), !blank(!incr)))
!doend
!enddefine.

If the condition is removed, it works correctly. 

Could you please help me correcting my code?

Thanks in advance!