Generate a sequence over the range of a vector

Usage

seq_range(x, n, by, trim = NULL, expand = NULL, pretty = FALSE)

Arguments

x

A numeric vector

n, by

Specify the output sequence either by supplying the length of the sequence with n, or the spacing between value with by. Specifying both is an error.

I recommend that you name these arguments in order to make it clear to the reader.

trim

Optionally, trim values off the tails. trim / 2 * length(x) values are removed from each tail.

expand

Optionally, expand the range by expand * (1 + range(x) (computed after trimming).

pretty

If TRUE, will generate a pretty sequence. If n is supplied, this will use pretty() instead of seq(). If by is supplied, it will round the first value to a multiple of by.

Examples

x <- rcauchy(100)
seq_range(x, n = 10)
#>  [1] -59.542807 -48.518955 -37.495103 -26.471252 -15.447400  -4.423548
#>  [7]   6.600303  17.624155  28.648007  39.671858
seq_range(x, n = 10, trim = 0.1)
#>  [1] -3.58894813 -2.36284623 -1.13674434  0.08935756  1.31545946
#>  [6]  2.54156135  3.76766325  4.99376515  6.21986704  7.44596894
seq_range(x, by = 1, trim = 0.1)
#>  [1] -3.5889481 -2.5889481 -1.5889481 -0.5889481  0.4110519  1.4110519
#>  [7]  2.4110519  3.4110519  4.4110519  5.4110519  6.4110519  7.4110519

# Make pretty sequences
y <- runif(100)
seq_range(y, n = 10)
#>  [1] 0.01080974 0.11995645 0.22910316 0.33824987 0.44739658 0.55654329
#>  [7] 0.66569000 0.77483671 0.88398342 0.99313012
seq_range(y, n = 10, pretty = TRUE)
#>  [1] 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
seq_range(y, n = 10, expand = 0.5, pretty = TRUE)
#>  [1] -0.4 -0.2  0.0  0.2  0.4  0.6  0.8  1.0  1.2  1.4

seq_range(y, by = 0.1)
#>  [1] 0.01080974 0.11080974 0.21080974 0.31080974 0.41080974 0.51080974
#>  [7] 0.61080974 0.71080974 0.81080974 0.91080974
seq_range(y, by = 0.1, pretty = TRUE)
#>  [1] 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0