Operators are those symbols which tell the computer to perform precise mathematical or logical manipulations. R programming is loaded with built in operators some of which are shown below:
We are going to learn about arithmetic operators using the following examples.
## Example
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# Let's first assign the variable x the value 5 and also assign the variable y the value 16.
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x <- 5
y <- 16
## Then, we add x and y together using the addition operator +
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x + y
## Challenge
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# Question: Using our understanding in the above example,
# let's now subtract x from y using the operator - below
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## Challenge
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# Question: Multiply x and y using the operator * below
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## Challenge
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# Question: Divide x by y using the operator / below
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## Challenge
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# Question: Get the modulo of y and x using the operator %% and print it out below
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## Challenge
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# Find the addition, substraction, multiplication, division, modulus of a and b when a = 10 and b = 4.
# Hint: Before we even start formulating a solution,
# lets assign the value 10 to variable a and assign the value 4 to a variable b.
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a <- 10
b <- 4
# Let's begin adding a and b as shown below
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a + b
# Then substracting a and b as shown below
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# Then multiplying a and b
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# Performing division of a and b
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# And lastly the modulo of a and b
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## Challenge
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# Question: Fix the code below to get an output of 1.
# Hint: You can change the values of the variables to get the output.
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c <- 10
d <- 2
c %% d
## Challenge
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# Question: Fix the code below to get an output of 25.
# Hint: You can change one of the operators to the subtraction operator - and get an answer
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a <- 5
b <- 4
b - a + 10 / 2 * a * 3 + 10 + 59
We are now going to learn about relational operators.
## Example
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# Question: Applying less than operator using the x and y variables
# Hint: For the following examples, we will use the previous assigned values of x and y using the operator <.
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# Lets find what x is
x
# Lets find what y is
y
# And now find out whether x is less than y.
x < y
## Challenge
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# Question: Find out whether x is greater than y using the Greater than operator >
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## Challenge
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# Question: Find whether x is less than or equal to y using the less than or equal to operator <=
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## Challenge
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# Question: Find out below whether x is greater than or equal to y using the greater than or equal to operator >= below
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## Challenge
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# Question: Find out whether y is equal to y using the equal to operator ==, below
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## Challenge
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# Question: Find out whether x is not equal to y using the not equal to operator !=, below
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Logical operators are applicable only to vectors of type logical, numeric or complex. Each element of the first vector is compared with the corresponding element of the second vector. The result of comparison is a Boolean value.
## Example
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# Question: Lets create two vectors v and t
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v <- c(3,1,TRUE,2+3i)
t <- c(4,1,FALSE,2+3i)
# Then use the element-wise logical and operator & as follows
v&t
## Example
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# Question: Create again two vectors v and t
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v <- c(0,0,TRUE,2+2i)
t <- c(0,3,TRUE,2+3i)
# Then use the element-wise logical or operator | below
v|t
## Example
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# Question: Let create two vectors v and t
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v <- c(3,1,TRUE,2+3i)
t <- c(4,1,FALSE,2+3i)
# This time, use the logical not operator ||
v||t
## Example
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# Question: Create two vectors v and t then use the logical AND operator
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v <- c(3,1,TRUE,2+3i)
t <- c(4,1,FALSE,2+3i)
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## Example
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# Question: Create variables v1, v2 and v3, assigning them with vectors
# using the left assignment operators v1, v2 and v3
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v1 <- c(3,1,TRUE,2+3i)
v2 <<- c(3,1,TRUE,2+3i)
v3 = c(3,1,TRUE,2+3i)
# Then we print out v1 below
v1
# And print out v2 below
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# And now print out v3 below
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## Challenge
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# Question: Use the right asignment operators to assign vectors to the variables v1 and v2
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c(3,1,TRUE,2+3i) -> v1
c(3,1,TRUE,2+3i) ->> v2
# Then print out variable v1 and see what has happened
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# And also print out variable v2
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Variables can be assigned values using leftward, rightward and equal to operator.
## Example
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# Question: Use the right assignment operators to assign the vectors to the respective variables as shown below;
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variable.1 = c(3,4,5,6)
variable.2 <- c("Hello"," there")
c(TRUE,2) -> variable.3
# Uncomment the following lines to see what has happened
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# variable.1
# variable.2
# variable.3
There are several basic data types in R which are of frequent occurrence.
## Example
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# Question: To learn about the numeric data type,
# lets assign the value 62.4 to the variable m as shown below
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m = 62.4
# Print out the variable's value below
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Assigning a decimal value for any variable m, m will become a numeric type as shown above.
Any integer in R is created by invoking the as.integer() function as shown below:
## Example
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# Let's now create an integer 3 and assign it to the variable n
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n = as.integer(3)
# Then print n below so as to see what is stored in n
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n
# Using another example, lets create convert 3.14 to an interger
# and assign the converted value to the variable p
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# And print out the value p so as to see the value that has been assigned to p
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## Example
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# We can also assign a complex number and assign it to the variable k just as shown below
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k = 1 + 2i
# Now lets print out k below
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A logical value is created when comparison between variables is done as shown:
## Example
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# To create a logical value we are first going to create two variables x and y variables
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x = 4; y = 6
# Now we check whether x is greater than y
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z = x > y
# And then print out the logical value below
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A character value can also be created and stored in a variable g.
## Example
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# Convert the value 62.48 to a string and store it a variable g
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g = as.character(62.48)
# Then print the character string g
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