Chop using pretty breakpoints

chop_pretty() uses base::pretty() to calculate breakpoints which are 1, 2 or 5 times a power of 10. These look nice in graphs.

Usage

chop_pretty(x, n = 5, ...)

brk_pretty(n = 5, ...)

tab_pretty(x, n = 5, ...)

Arguments

x

A vector.

n

Positive integer passed to base::pretty(). How many intervals to chop into?

...

Passed to chop() by chop_pretty() and tab_pretty(); passed to base::pretty() by brk_pretty().

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

base::pretty() tries to return n+1 breakpoints, i.e. n intervals, but note that this is not guaranteed. There are methods for Date and POSIXct objects.

For fine-grained control over base::pretty() parameters, use chop(x, brk_pretty(...)).

Examples

chop_pretty(1:10)
#>  [1] [0, 2)  [2, 4)  [2, 4)  [4, 6)  [4, 6)  [6, 8)  [6, 8)  [8, 10] [8, 10]
#> [10] [8, 10]
#> Levels: [0, 2) [2, 4) [4, 6) [6, 8) [8, 10]

chop(1:10, brk_pretty(n = 5, high.u.bias = 0))
#>  [1] [1, 2)  [2, 3)  [3, 4)  [4, 5)  [5, 6)  [6, 7)  [7, 8)  [8, 9)  [9, 10]
#> [10] [9, 10]
#> Levels: [1, 2) [2, 3) [3, 4) [4, 5) [5, 6) [6, 7) [7, 8) [8, 9) [9, 10]

tab_pretty(1:10)
#>  [0, 2)  [2, 4)  [4, 6)  [6, 8) [8, 10] 
#>       1       2       2       2       3