7.4 Exercice 1. Getting started.

Create the script “exercise1.R” (in R Studio: File -> New File) and save it to the “Rcourse/Module1” directory: you will save all the commands of exercise 1 in that script.
Remember you can comment the code using #.

1- From the terminal, go to Rcourse/Module1. First check where you currently are with getwd(); then go to Rcourse/Module1 with setwd()

correction

getwd()
setwd("Rcourse/Module1")
setwd("~/Rcourse/Module1")

2- Using R as a calculator, calculate the square root of 654.

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sqrt(654)

## [1] 25.57342

3- Using R as a calculator, calculate the percentage of males and females currently present in the classroom.

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# 6 males out of 19 students:
(6/19) * 100

## [1] 31.57895

# 13 females out of 19 students
(13/19) * 100

## [1] 68.42105

4- Create a new object “myobject” with value 60. Show “myobject” in the terminal.

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myobject <- 60
myobject

## [1] 60

5- Reassign myobject with value 87.

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myobject <- 87

6- Subtract 1 to myobject. Reassign.

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myobject <- myobject - 1

7- Create a new object “mysqrt” that will store the square root of “myobject”.

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mysqrt <- sqrt(myobject)

8- Create a new object “mydiv” that will store the result of “myobject” divided by “mysqrt”.

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mydiv <- myobject / mysqrt