Error with summarise

tl=filter(climate_full,as.numeric(Year)>1959)
 t2=arrange(tl,desc(AirTemp_Mean))
 t2=t2[1:100,]
t3=group_by(t2,Year)
 t3=summarise(t3,ndays=())
Error: unexpected ')' in "t3=summarise(t3,ndays=()"
 qplot(data=t2,x=Year,y=ndays,geom="point")

i have tried again and again to find a slolution with the () but Rstudio always replies with Error: unexpected ')' in "t3=summarise(t3,ndays=()"

do you mean summarise(t3, ndays = n() ) ?

Sorry for taking your time I just found the solution I only had to leave a space between the parentheses in ndays() ). Thank you for your time.

Yes that is what I mean. Before you say that the solution is just to add another ), think again I have tried 50 times it always replies Error: unexpected ')' in "t3=summarise(t3,ndays=()" I believe the problem lies with the last 2 )). Thanks for the quick reply.