[R] printing difftime summary

[David Winsemius]

On Nov 26, 2012, at 7:14 AM, Sam Steingold wrote:

> this overcomes the summary generation, but not printing:
>
> --8<---------------cut here---------------start------------->8---
> summary.difftime <- function (v, ...) {
>  s <- summary(as.numeric(v), ...)
>  r <- as.data.frame(sapply(s,difftime2string),stringsAsFactors=FALSE)
>  names(r) <- c("string")
>  r[[units(v)]] <- s
>  class(r) <- c("data.frame","summary.difftime")
>  r
> }
> print.summary.difftime <- function (sd) print.data.frame(sd)
> --8<---------------cut here---------------end--------------->8---
>
> summary(infl), where infl$delay is a difftime vector, prints
>
> ...
>
>    delay
> string:c("492.00 ms", "18.08 min", "1.77 hrs", "8.20 hrs", "8.13  
> hrs", "6.98 days")
> secs  :c("     0.5", "  1085.1", "  6370.2", " 29534.4", " 29254.0",  
> "602949.7")
>
>
>
> instead of something like
>
>   delay
>   Min.:    492 ms
>   1st Qu.: 18.08 min
>
> &c
>
> so, how do I arrange for a proper printing of difftime summary as a  
> part
> of the data frame summary?

If you like a particular format from an existing print method then why  
not look it up and copy the code?

methods(print)

-- 
David.
>
>> * David Winsemius <qjvafrzvhf at pbzpnfg.arg> [2012-11-25 00:50:51  
>> -0800]:
>>
>> On Nov 24, 2012, at 7:48 PM, Sam Steingold wrote:
>>
>>>> * David Winsemius <qjvafrzvhf at pbzpnfg.arg> [2012-11-23 13:14:17
>>>> -0800]:
>>>>
>>>>>> See http://cran.r-project.org/doc/FAQ/R-FAQ.html#How-should-I-write-summary-methods_003f
>>>
>>> --8<---------------cut here---------------start------------->8---
>>> summary.difftime <- function (v) {
>>> s <- summary(as.numeric(v))
>>> r <- as.data.frame(sapply(s,difftime2string),stringsAsFactors=FALSE)
>>> names(r) <- c("string")
>>> r[[units(v)]] <- s
>>> class(r) <- c("data.frame","summary.difftime")
>>> r
>>> }
>>> print.summary.difftime <- function (sd) print.data.frame(sd)
>>> --8<---------------cut here---------------end--------------->8---
>>>
>>> it appears to work for a single vector:
>>>
>>> --8<---------------cut here---------------start------------->8---
>>>> r1 <- summary(infl$delay)
>>>> r1
>>>          string     secs
>>> Min.    492.00 ms      0.5
>>> 1st Qu. 18.08 min   1085.0
>>> Median   1.77 hrs   6370.0
>>> Mean     8.20 hrs  29530.0
>>> 3rd Qu.  8.12 hrs  29250.0
>>> Max.    6.98 days 602900.0
>>>> str(r1)
>>> Classes 'summary.difftime' and 'data.frame':	6 obs. of  2 variables:
>>> $ string: chr  "492.00 ms" "18.08 min" "1.77 hrs" "8.20 hrs" ...
>>> $ secs  :Classes 'summaryDefault', 'table'  num [1:6] 4.92e-01
>>> 1.08e+03 6.37e+03 2.95e+04 2.92e+04 ...
>>> --8<---------------cut here---------------end--------------->8---
>>>
>>> but not as a part of data frame:
>>>
>>> --8<---------------cut here---------------start------------->8---
>>>> a <- summary(infl)
>>> Error in summary.difftime(X[[22L]], ...) :
>>> unused argument(s) (maxsum = 7, digits = 12)
>>> --8<---------------cut here---------------end--------------->8---
>>>
>>> I guess I should somehow accept a list of options in
>>> summary.difftime()
>>> and pass them on to the inner call to summary() (or should it be
>>> explicitly summary.numeric()?)
>>>
>>
>> In the usual way. If you know that the function will be called with
>> arguments from the summary.data.frame function then you should  
>> allow the
>> argument list to accept them. You can ignore them or provide  
>> provisions
>> for them. You just can't define your function to have only one  
>> argument
>> if you expect (as you should since you passes summary a dataframe
>> object) that it might be called within summary.data.frame.
>>
>> This is the argument list for summary.data.frame:
>>
>>>  summary.data.frame
>> function (object, maxsum = 7, digits = max(3, getOption("digits") -
>>    3), ...)
>>
>>> how do I do that?
>>
>> summary.difftime <- function (v, ... ) { ................
>>
>> There are many asked and answered questions on rhelp about how to  
>> deal
>> with the "dots" arguments.
>
> -- 
> Sam Steingold (http://sds.podval.org/) on Ubuntu 12.04 (precise) X  
> 11.0.11103000
> http://www.childpsy.net/ http://www.memritv.org http://memri.org
> http://honestreporting.com http://dhimmi.com http://openvotingconsortium.org
> People with a good taste are especially appreciated by cannibals.

David Winsemius, MD
Alameda, CA, USA