R, knitr, pander - How to nicely format summary() of dates

Question

I am using summary() to generate simple summaries of date variables in a knitr document and want to have the results nicely formatted.

summary(some_date)

produces the results I want (the values are displayed as dates) but it is not nicely formatted. So, I tried:

pander::pander(summary(some_date))

This produces nicely formatted results, but the values are displayed as integers instead of dates. (This is true for Date, POSIXct, and POSIXlt dates).

Is there some way to nicely format the results of a summary() of dates in a knitr document? Maybe there is some package other than pander which is better for this task.

Examples below:

summary(some_date)
##         Min.      1st Qu.       Median         Mean      3rd Qu. 
## "2014-05-01" "2015-02-15" "2015-06-17" "2015-05-05" "2015-09-08" 
##         Max. 
## "2015-11-21"

pander::pander(summary(some_date))
Min.    1st Qu. Median  Mean    3rd Qu. Max.
16191   16481   16603   16560   16686   16760

sessionInfo()
## R version 3.2.3 (2015-12-10)
## Platform: x86_64-pc-linux-gnu (64-bit)
## Running under: Ubuntu 14.04.3 LTS
## 
## locale:
##  [1] LC_CTYPE=en_AU.UTF-8       LC_NUMERIC=C              
##  [3] LC_TIME=en_AU.UTF-8        LC_COLLATE=en_AU.UTF-8    
##  [5] LC_MONETARY=en_AU.UTF-8    LC_MESSAGES=en_AU.UTF-8   
##  [7] LC_PAPER=en_AU.UTF-8       LC_NAME=C                 
##  [9] LC_ADDRESS=C               LC_TELEPHONE=C            
## [11] LC_MEASUREMENT=en_AU.UTF-8 LC_IDENTIFICATION=C       
## 
## attached base packages:
## [1] stats     graphics  grDevices utils     datasets  methods   base     
## 
## other attached packages:
## [1] pander_0.6.0  ggplot2_2.0.0 daff_0.1.4    magrittr_1.5  dplyr_0.4.3  
## [6] readr_0.2.2  
## 
## loaded via a namespace (and not attached):
##  [1] Rcpp_0.12.2      knitr_1.11       munsell_0.4.2    lattice_0.20-33 
##  [5] colorspace_1.2-6 R6_2.1.1         plyr_1.8.3       stringr_1.0.0   
##  [9] tools_3.2.3      parallel_3.2.3   grid_3.2.3       packrat_0.4.6-4 
## [13] nlme_3.1-122     gtable_0.1.2     mgcv_1.8-7       DBI_0.3.1       
## [17] htmltools_0.2.6  lazyeval_0.1.10  yaml_2.1.13      assertthat_0.1  
## [21] digest_0.6.8     Matrix_1.2-3     formatR_1.2.1    curl_0.9.4      
## [25] evaluate_0.8     rmarkdown_0.9    labeling_0.3     V8_0.9          
## [29] stringi_1.0-1    scales_0.3.0     jsonlite_0.9.19

Answer 1

Thanks for the bug report, with the development version of pander it should now render correctly:

> pander::pander(summary(as.Date('2015-01-01') + 1:100))

-----------------------------------------------------------------
   Min.     1st Qu.     Median      Mean     3rd Qu.      Max.   
---------- ---------- ---------- ---------- ---------- ----------
2015-01-02 2015-01-26 2015-02-20 2015-02-20 2015-03-17 2015-04-11
-----------------------------------------------------------------