xts (version 0.13.1)

axTicksByTime: Compute x-Axis Tickmark Locations by Time

Description

Compute x-axis tickmarks like axTicks in base but with respect to time. Additionally the first argument is the object indexed by time which you are looking to derive tickmark locations for.

It is possible to specify the detail you are seeking, or by passing 'auto' to the ticks.on argument, to get a best heuristic fit.

Usage

axTicksByTime(x, ticks.on='auto', k = 1,
              labels=TRUE, format.labels=TRUE, ends=TRUE,
              gt = 2, lt = 30)

Value

A numeric vector of index element locations where tick marks should be drawn. These are locations (e.g. 1, 2, 3, ...), not the index timestamps.

If possible, the result will be named using formatted values from the index timestamps. The names will be used for the tick mark labels.

Arguments

x

the object indexed by time, or a vector of times/dates

ticks.on

what to break on

k

frequency of breaks

labels

should a labeled vector be returned

format.labels

format labels - may be format to use

ends

should the ends be adjusted

gt

lower bound on number of breaks

lt

upper bound on number of breaks

Author

Jeffrey A. Ryan

Details

This function is written for internal use, and documented for those wishing to use outside of the internal function uses. In general it is most unlikely that the end user will call this function directly.

The format.labels argument allows for standard formatting like that used in format, strptime, and strftime.

See Also

endpoints

Examples

data(sample_matrix)
axTicksByTime(as.xts(sample_matrix),'auto')
axTicksByTime(as.xts(sample_matrix),'weeks')
axTicksByTime(as.xts(sample_matrix),'months',7)