A easy problem. Help!

Hi,

Would you tell me why the procedure below appears this error "Duplicate/O fluorescence, fluortemp" ? Thanks a lot.

Function test1()
Duplicate/O fluorescence, fluortemp
Wave fluorescence
fluortemp = fluorescence/3
End
You need to declare the Wave fluorescence before Duplicate, so that Igor knows that there is a wave called "fluorescence" that it must duplicate.

Function test1()

    Wave fluorescence
    Duplicate/O fluorescence, fluortemp
    fluortemp = fluorescence/3
   
End