Lower Limits, Midpoints, and Upper Limits of Age Groups

Given a vector x of age group labels, return a numeric vector.

age_lower() returns the lower limits of each age group,
age_mid() returns the midpoints, and
age_upper() returns the upper limits.

Vector x must describe 1-year, 5-year or life-table age groups: see age_labels() for examples. x can format these age groups in any way understood by reformat_age().

Usage

age_lower(x)

age_mid(x)

age_upper(x)

Arguments

x: A vector of age group labels.

Value

A numeric vector, the same length as x.

Details

These functions can make age groups easier to work with. Lower and upper limits can be used for selecting on age. Replacing age group with midpoints can improve graphs.

Examples

x <- c("15-19", "5-9", "50+")
age_lower(x)
#> [1] 15  5 50
age_mid(x)
#> [1] 17.5  7.5 52.5
age_upper(x)
#> [1]  20  10 Inf

## non-standard formats are OK
age_lower(c("infants", "100 and over"))
#> [1]   0 100

df <- data.frame(age = c("1-4", "10-14", "5-9", "0"),
                 rate = c(0.023, 0.015, 0.007, 0.068))
df
#>     age  rate
#> 1   1-4 0.023
#> 2 10-14 0.015
#> 3   5-9 0.007
#> 4     0 0.068
subset(df, age_lower(age) >= 5)
#>     age  rate
#> 2 10-14 0.015
#> 3   5-9 0.007