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You can use the following basic syntax to write a for-loop with a range in R:

for(i in 1:10) { do something }

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

**Example 1: Print Values in Range**

The following code shows how to use a for-loop to print every value in a certain range:

#print every value in range of 1 to 10 for(i in 1:10) { print(i) } [1] 1 [1] 2 [1] 3 [1] 4 [1] 5 [1] 6 [1] 7 [1] 8 [1] 9 [1] 10

**Example 2: Perform Operation on Values in Range**

The following code shows how to use a for-loop to perform a specific operation on every value in a certain range:

#define vector x #print square root of every value in vector for(i in 1:length(x)) { print(paste('The square root of the value in position', i, 'is', sqrt(x[i]))) } [1] "The square root of the value in position 1 is 2" [1] "The square root of the value in position 2 is 2.64575131106459" [1] "The square root of the value in position 3 is 3" [1] "The square root of the value in position 4 is 3.46410161513775" [1] "The square root of the value in position 5 is 3.74165738677394" [1] "The square root of the value in position 6 is 4" [1] "The square root of the value in position 7 is 4.35889894354067"

**Example 3: Perform Operation on Values in Data Frame**

The following code shows how to use a for-loop to perform a specific operation on every value in a specific column of a data frame in r:

#define data frame df frame(a=c(3, 4, 4, 5, 8), b=c(8, 8, 7, 8, 12), c=c(11, 15, 19, 15, 11)) #view data frame df a b c 1 3 8 11 2 4 8 15 3 4 7 19 4 5 8 15 5 8 12 11 #multiply every value in column 'a' by 2 for(i in 1:length(df$a)) { df$a[i] = df$a[i]*2 } #view updated data frame df a b c 1 6 8 11 2 8 8 15 3 8 7 19 4 10 8 15 5 16 12 11

**Additional Resources**

How to Create a Nested For Loop in R

How to Write a Nested If Else Statement in R

How to Loop Through Column Names in R