Follow the example to see the use of na.rm=T in R

**> x=c(0, 1, 1, 2, 3, 5, 8) #vector**

**> x**

**[1] 0 1 1 2 3 5 8**

**> mean(x)**

**[1] 2.857143**

Now, introduce a NA value in our vector.

**> x=c(0, 1, 1, 2, 3, 5, 8,NA)**

**> mean(x)**

**[1] NA # mean does not work!**

**> mean(x,na.rm=T) #Try removing NA for mean.**

**[1] 2.857143**