R language has many built in functions, in which statistical functions are mostly used on numeric vectors.
sum(x) – The sum of vector x
min(x) – The Minimum value of vector x
max(x) – The maximum value of vector x
mean(x) – The arithmetic mean of vector x
median(x) – The median of numeric vector x. 50% of data should be less than median and balance 50% data should be greater than median.
sd(x) – The standard deviation of vector x
var(x) – The Variance of numeric vector x
quantile(x,p) – The Pth sample quantile of numeric vector x. for example, quantile(x,.3) will tell us the value at which 30% of cases are less than value x.
summary(x) – It shows several statistics of vector x, including the above.