Important Operators
Comparison operators
==(equal)!=(not equal)>(greater than)>=(greater than or equal)<(less than)<=(less than or equal)
Logical operators
&(and)|(or)!(not)
Conditional Executions: if Statements
An if statement operates on length-one logical vectors.
Syntax
if(TRUE) {
statements_1
} else {
statements_2
}
Example
if(1==0) {
print(1)
} else {
print(2)
}
## [1] 2
Conditional Executions: ifelse Statements
The ifelse statement operates on vectors.
Syntax
ifelse(test, true_value, false_value)
Example
x <- 1:10
ifelse(x<5, x, 0)
## [1] 1 2 3 4 0 0 0 0 0 0