Conditions
- Seen conditions before when filtering data
10 > 5
"aang" == "aang"
3 != 3
-
Conditions return
TRUEif the condition is satisfied,FALSEif not -
Can combine conditions using
andand `or
5 > 2 & 6 >=10
5 > 2 | 6 >=10
Exercise 1
Did you notice anything weird?
Floating point
> x <- 1.3
> y <- 2.8
> x * 2 + 0.2 == y
[1] FALSE
> 1.3 * 2 + 0.2
[1] 2.8
- What’s going on?
- See this more easily in Python
>>> 1.3 * 2 + 0.2 == 2.8
False
>>> 1.3 * 2 + 0.2
2.8000000000000003
all.equal(x * 2 + 0.2, y)
Conditionals
- In addition to using conditions with other functions to filter data we can use
them directly using
ifstatements
superhero <- "Black Widow"
if (superhero == "Batman"){
print("That is correct")
}
print("Done")
superhero <- "Black Widow"
if (superhero == "Batman"){
print("That is correct")
} else {
print("Please try again")
}
print("Done)
superhero <- "Black Widow"
if (superhero == "Batman"){
print("That is correct")
} else if (superhero == "Black Widow") {
print("OK, you may have a point")
} else {
print("Please try again")
}
print("Done")
- Then switch to
Flash
Convert to function
is_best_superhero <- function(superhero){
if (superhero == "Batman"){
print("That is correct")
} else if (superhero == "Black Widow") {
print("OK, you may have a point")
} else {
print("Please try again")
}
}
is_best_superhero("Hulk")
- Realize hulk is awesome and add to Black Widow line
Exercise 2