Fonction DATEDIFF not working

[ELYATIM]

Hello All, 

i have a issue to use the function DATEDIFF

this is an example of the data table 

 Data 4 is a Mesure, and i want to use inside the function, but i cannot selected 

example : 

IF(Data 4 = Mesure,DATEDIFF(DATA1-DATA2),(DATA1-DATA3))

your helpl will be appreciated please 

thanks 

[Anonymous]

@ELYATIM  My bad 
but you still need to follow the syntax DATEDIF(Start_date,End_date,"Y")     
You can start date and end date and you need to select the interval as well
If you can provide little more context maybe I can be any help.

[ELYATIM]

the problem is not DATEDIFF, im trying to use this function under a conditon 

for example if ( the mesure value = A, DATEDIFF(date1,date2,day))

bur is not working. i cant add the mesure to the function 

[ELYATIM]

i think you confusing the function DATEADD and DATEDIFF