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You can use the **sqrt()** function to find the square root of a numeric value in R:

sqrt(x)

The following examples show how to use this function in practice.

**Example 1: Calculate Square Root of a Single Value**

The following code shows how to calculate the square root of a single value in R:

#define x x #find square root of x sqrt(x) [1] 5

**Example 2: Calculate Square Root of Values in Vector**

The following code shows how to calculate the square root of every value in a vector in R:

#define vector x #find square root of every value in vector sqrt(x) [1] 1.000000 1.732051 2.000000 2.449490 3.000000 3.741657 4.000000 5.000000

Note that if there are negative values in the vector, there will be a warning message. To avoid this warning message, you can first convert each value in the vector to an absolute value:

#define vector with some negative values x #attempt to find square root of each value in vector sqrt(x) [1] 1.000000 1.732051 2.000000 2.449490 NaN 3.741657 NaN 5.000000 Warning message: In sqrt(x) : NaNs produced #convert each value to absolute value and then find square root of each value sqrt(abs(x)) [1] 1.000000 1.732051 2.000000 2.449490 3.000000 3.741657 4.000000 5.000000

**Example 3: Calculate Square Root of Column in Data Frame**

The following code shows how to calculate the square root of a single column in a data frame:

#create data frame data frame(a=c(1, 3, 4, 6, 8, 9), b=c(7, 8, 8, 7, 13, 16), c=c(11, 13, 13, 18, 19, 22), d=c(12, 16, 18, 22, 29, 38)) #find square root of values in column a sqrt(data$a) [1] 1.000000 1.732051 2.000000 2.449490 2.828427 3.000000

**Example 4: Calculate Square Root of Several Columns in Data Frame**

The following code shows how to use the **apply()** function to calculate the square root of several columns in a data frame:

#create data frame data frame(a=c(1, 3, 4, 6, 8, 9), b=c(7, 8, 8, 7, 13, 16), c=c(11, 13, 13, 18, 19, 22), d=c(12, 16, 18, 22, 29, 38)) #find square root of values in columns a, b, and d apply(data[ , c('a', 'b', 'd')], 2, sqrt) a b d [1,] 1.000000 2.645751 3.464102 [2,] 1.732051 2.828427 4.000000 [3,] 2.000000 2.828427 4.242641 [4,] 2.449490 2.645751 4.690416 [5,] 2.828427 3.605551 5.385165 [6,] 3.000000 4.000000 6.164414

**Additional Resources**

How to Transform Data in R (Log, Square Root, Cube Root)

How to Calculate Root Mean Square Error (RMSE) in R