chop_n() creates intervals containing a fixed number of elements.
Usage
chop_n(x, n, ..., close_end = TRUE, tail = "split")
brk_n(n, tail = "split")
tab_n(x, n, ..., tail = "split")Arguments
- x
A vector.
- n
Integer. Number of elements in each interval.
- ...
Passed to
chop().- close_end
Logical. Close last break at right? (If
leftisFALSE, close first break at left?)- tail
String. What to do if the final interval has fewer than
nelements?"split"to keep it separate."merge"to merge it with the neighbouring interval.
Value
chop_* functions return a factor of the same length as x.
brk_* functions return a function to create breaks.
tab_* functions return a contingency table().
Details
The algorithm guarantees that intervals contain no more than n elements, so
long as there are no duplicates in x and tail = "split". It also
guarantees that intervals contain no fewer than n elements, except possibly
the last interval (or first interval if left is FALSE).
To ensure that all intervals contain at least n elements (so long as there
are at least n elements in x!) set tail = "merge".
If tail = "split" and there are intervals containing duplicates with more
than n elements, a warning is given.
See also
Other chopping functions:
chop(),
chop_equally(),
chop_evenly(),
chop_fn(),
chop_mean_sd(),
chop_proportions(),
chop_quantiles(),
chop_width(),
fillet()
Examples
chop_n(1:10, 5)
#> [1] [1, 6) [1, 6) [1, 6) [1, 6) [1, 6) [6, 10] [6, 10] [6, 10] [6, 10]
#> [10] [6, 10]
#> Levels: [1, 6) [6, 10]
chop_n(1:5, 2)
#> [1] [1, 3) [1, 3) [3, 5) [3, 5) {5}
#> Levels: [1, 3) [3, 5) {5}
chop_n(1:5, 2, tail = "merge")
#> [1] [1, 3) [1, 3) [3, 5] [3, 5] [3, 5]
#> Levels: [1, 3) [3, 5]
# too many duplicates
x <- rep(1:2, each = 3)
chop_n(x, 2)
#> Warning: Some intervals contain more than 2 elements
#> [1] [1, 2) [1, 2) [1, 2) {2} {2} {2}
#> Levels: [1, 2) {2}
tab_n(1:10, 5)
#> [1, 6) [6, 10]
#> 5 5
# fewer elements in one group
tab_n(1:10, 4)
#> [1, 5) [5, 9) [9, 10]
#> 4 4 2