Return the number of observations

Returns the number of observations of a vector or data.frame. It uses vctrs::vec_size() under the hood.

n_obs(x, names = TRUE)

Arguments

x	vector or data.frame
names	logical; If TRUE the result is a named vector named "n_obs", else it is just the number of observations.

Value

number of observations

Note

You cannot use n_obs with features counting the key variable like so - features(heights, country, n_obs). Instead, use any other variable.

Examples

n_obs(iris)
#> n_obs 
#>   150 
n_obs(1:10)
#> n_obs 
#>    10 
add_n_obs(heights)
#> # A tsibble: 1,490 x 5 [!]
#> # Key:       country [144]
#>    country      year n_obs continent height_cm
#>    <chr>       <dbl> <int> <chr>         <dbl>
#>  1 Afghanistan  1870     5 Asia           168.
#>  2 Afghanistan  1880     5 Asia           166.
#>  3 Afghanistan  1930     5 Asia           167.
#>  4 Afghanistan  1990     5 Asia           167.
#>  5 Afghanistan  2000     5 Asia           161.
#>  6 Albania      1880     4 Europe         170.
#>  7 Albania      1890     4 Europe         170.
#>  8 Albania      1900     4 Europe         169.
#>  9 Albania      2000     4 Europe         168.
#> 10 Algeria      1910     5 Africa         169.
#> # … with 1,480 more rows
heights %>%
  features(height_cm, n_obs) # can be any variable except id, the key.
#> # A tibble: 144 x 2
#>    country     n_obs
#>    <chr>       <int>
#>  1 Afghanistan     5
#>  2 Albania         4
#>  3 Algeria         5
#>  4 Angola          9
#>  5 Argentina      20
#>  6 Armenia        11
#>  7 Australia      10
#>  8 Austria        18
#>  9 Azerbaijan      7
#> 10 Bahrain         3
#> # … with 134 more rows