Check if values are sorted — is

Check if values are sorted in increasing order from left to right.

Usage

is_sorted(...)

Arguments

...: One vector, or multiple vectors of the same length.

Value

If there is one input, a logical value. If there are multiple inputs, a logical vector the same length as the inputs.

Details

Any number of vectors can be compared. If the input is a single vector, the order of elements in that vector is checked. However, if the input is multiple vectors, the order of elements across all vectors at each index is checked. NAs are ignored.

Examples

is_sorted(letters)
#> [1] TRUE

is_sorted(rev(letters))
#> [1] FALSE

x <- 1:5
y <- c(2, 3, NA, 0, 5)
is_sorted(x, y)
#> [1]  TRUE  TRUE  TRUE FALSE  TRUE

df <- data.frame(
  d1 = seq.Date(
    as.Date("1980-01-01"),
    as.Date("1980-12-31"),
    by = "month"
  ),
  d2 = seq.Date(
    as.Date("1990-01-01"),
    as.Date("1990-12-31"),
    by = "month"
  ),
  d3 = seq.Date(
    as.Date("1985-01-01"),
    as.Date("1996-01-01"),
    by = "year"
  )
)

df$sorted <- is_sorted(df$d1, df$d2, df$d3)

df
#>            d1         d2         d3 sorted
#> 1  1980-01-01 1990-01-01 1985-01-01  FALSE
#> 2  1980-02-01 1990-02-01 1986-01-01  FALSE
#> 3  1980-03-01 1990-03-01 1987-01-01  FALSE
#> 4  1980-04-01 1990-04-01 1988-01-01  FALSE
#> 5  1980-05-01 1990-05-01 1989-01-01  FALSE
#> 6  1980-06-01 1990-06-01 1990-01-01  FALSE
#> 7  1980-07-01 1990-07-01 1991-01-01   TRUE
#> 8  1980-08-01 1990-08-01 1992-01-01   TRUE
#> 9  1980-09-01 1990-09-01 1993-01-01   TRUE
#> 10 1980-10-01 1990-10-01 1994-01-01   TRUE
#> 11 1980-11-01 1990-11-01 1995-01-01   TRUE
#> 12 1980-12-01 1990-12-01 1996-01-01   TRUE