You can use the following basic syntax to calculate the standard deviation of columns in R:

#calculate standard deviation of one column sd(df$col1) #calculate standard deviation of all columns sapply(df, sd) #calculate standard deviation of specific columns sapply(df[c('col1', 'col2', 'col5')], sd)

The following examples show how to use this syntax in practice with the following data frame:

#create data frame df <- data.frame(team=c('A', 'B', 'C', 'D', 'E'), points=c(99, 91, 86, 88, 95), assists=c(33, 28, 31, 39, 34), rebounds=c(30, 28, 24, 24, 28)) #view data frame df team points assists rebounds 1 A 99 33 30 2 B 91 28 28 3 C 86 31 24 4 D 88 39 24 5 E 95 34 28

**Example 1: Standard Deviation of One Column**

The following code shows how to calculate the standard deviation of one column in the data frame:

#calculate standard deviation of 'points' column sd(df$points) [1] 5.263079

The standard deviation of values in the ‘points’ column is **5.263079**.

**Example 2: Standard Deviation of All Columns**

The following code shows how to calculate the standard deviation of every column in the data frame:

#calculate standard deviation of all columns in data frame sapply(df, sd) team points assists rebounds NA 5.263079 4.062019 2.683282 Warning message: In var(if (is.vector(x) || is.factor(x)) x else as.double(x), na.rm = na.rm) : NAs introduced by coercion

Since the ‘team’ column is a character variable, R returns NA and gives us a warning.

However, it successfully computes the standard deviation of the other three numeric columns.

**Example 3: Standard Deviation of Specific Columns**

The following code shows how to calculate the standard deviation of specific columns in the data frame:

#calculate standard deviation of 'points' and 'rebounds' columns sapply(df[c('points', 'rebounds')], sd) points rebounds 5.263079 2.683282

Note that we could use column index values to select columns as well:

#calculate standard deviation of 'points' and 'rebounds' columns sapply(df[c(2, 4)], sd) points rebounds 5.263079 2.683282

**Additional Resources**

The following tutorials explain how to perform other common functions on columns in R:

How to Calculate the Mean of Multiple Columns in R

How to Find the Max Value Across Multiple Columns in R

How to Select Specific Columns in R