R - Standard Deviation

The R sd() function returns standard deviation of all elements present in the argument. The syntax for using this function is given below:

Syntax

sd(x, na.rm = FALSE)

Parameters

`x`	`Required.` Specify numeric vector.
`na.rm`	`Optional.` Specify TRUE to remove NA or NaN values before the computation. Default is FALSE.

Return Value

Returns standard deviation of all elements present in the argument.

Example:

The example below shows the usage of sd() function.

vec <- c(10, 55, 25, -56, 30, 99)
cat("Standard deviation of all elements of vec:", sd(vec), "\n")

mat <- matrix(c(10, 55, 25, -56, 30, 99), ncol=2)
cat("\nThe matrix contains:\n")
print(mat)
cat("Standard deviation of all elements of mat:", sd(mat))
cat("\nStandard deviation of elements along first column:", sd(mat[,1]))

The output of the above code will be:

Standard deviation of all elements of vec: 51.30075 

The matrix contains:
     [,1] [,2]
[1,]   10  -56
[2,]   55   30
[3,]   25   99
Standard deviation of all elements of mat: 51.30075
Standard deviation of elements along first column: 22.91288

Using na.rm parameter

The na.rm parameter can be set TRUE to remove NA or NaN values before the computation.

Example:

Consider the example below to see the usage of na.rm parameter.

v1 <- c(10, 55, 25, -56, 30, 99, NA)
v2 <- c(10, 55, 25, -56, 30, 99, NaN)

cat("Standard deviation of all elements of v1:", sd(v1), "\n")
cat("Standard deviation after removing NA:", sd(v1, na.rm=TRUE), "\n")

cat("\nStandard deviation of all elements of v2:", sd(v2), "\n")
cat("Standard deviation after removing NaN:", sd(v2, na.rm=TRUE), "\n")

The output of the above code will be:

Standard deviation of all elements of v1: NA 
Standard deviation after removing NA: 51.30075 

Standard deviation of all elements of v2: NA 
Standard deviation after removing NaN: 51.30075

❮ R Statistical Functions