We use square brackets to access specific elements of a vector. For the vector codes we defined above, we can access the second element using:
codes[2]
#> canada
#> 124You can get more than one entry by using a multi-entry vector as an index:
codes[c(1,3)]
#> italy egypt
#> 380 818The sequences defined above are particularly useful if we want to access, say, the first two elements:
codes[1:2]
#> italy canada
#> 380 124If the elements have names, we can also access the entries using these names. Below are two examples.
codes["canada"]
#> canada
#> 124
codes[c("egypt","italy")]
#> egypt italy
#> 818 380
# Make codes vector with names of country.
codes <- c(380, 124, 818)
country <- c("italy","canada","egypt")
names(codes) <- country
# You can access the second value in codes vector
codes[2]
# When you use two or more indexes, please use c function.
codes[c(1,3)]
# You can use : symbol for multiple indexing.
codes[1:2]
# You can use the assgined name to access the value.
codes["canada"]
# You can use the two or more assgined name to access the value.
codes[c("egypt","italy")]