Re: [R] histogram of dates

From: Marc Schwartz <marc_schwartz_at_me.com>
Date: Fri, 22 Apr 2011 12:49:38 -0500

On Apr 22, 2011, at 12:31 PM, Terry Therneau wrote:

> I can't seem to get a histogram of dates:
>
> tmt910% R --vanilla
>
> R version 2.13.0 (2011-04-13)
> Copyright (C) 2011 The R Foundation for Statistical Computing
> ISBN 3-900051-07-0
> ...

>> temp <- as.Date(1:200, origin="1970/01/01")
>> range(temp)

> [1] "1970-01-02" "1970-07-20"
>> hist(temp)

> Error in .Internal(inherits(x, what, which)) : 'x' is missing
>
>> traceback()

> 3: inherits(breaks, "Date")
> 2: hist.Date(temp)
> 1: hist(temp)
>
> Existence of hist.Date implies that this is intended to work.
> The MASS version fails in a different way.
>
>> library(MASS)
>> truehist(temp)

> Error in Ops.difftime(n, 2) : '%/%' not defined for "difftime" objects

Hi Terry,

Try this:

  temp <- as.Date(1:200, origin="1970/01/01")

  hist(temp, breaks = "months")

There is no default for the 'breaks' argument in hist.Date() and there does not appear to be a check for a missing value for this argument.

truehist() does not have a method for Date class objects, but you could do:

  truehist(as.numeric(temp))

or perhaps use cut.Date() on the vector and create the intervals/breakpoints that you wish to use.

HTH, Marc Schwartz



R-help_at_r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. Received on Fri 22 Apr 2011 - 17:53:46 GMT

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.2.0, at Fri 22 Apr 2011 - 18:00:32 GMT.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.

list of date sections of archive