as.Date yields NA for month name "März" (march)

Question

I got a scraped character vector with dates. My problem: When using `as.Date()`, every date containing the month name "März" (= which means "march" in German) is `NA` ed. Why is that? Here is an (hopefully reproducible) example: ``` require(RCurl) require(XML) doc <- htmlParse(getURL("http://www.amazon.de/product-reviews/3836218984/?ie=UTF8&pageNumber=5&showViewpoints=0&sortBy=byRankDescending"), encoding="UTF-8") (dates <- xpathSApply(doc, "//div/span[2]/nobr", xmlValue)) # [1] "12. Februar 2009" "12. November 2006" "19. März 2010" # [4] "30. Juni 2007" "7. März 2006" "19. März 2007" # [7] "22. Januar 2006" "24. September 2005" "15. Februar 2012" # [10] "28. März 2007" Sys.setlocale("LC_TIME", "German") # on Windows, see ?Sys.setlocale as.Date(dates, "%d. %B %Y") # [1] "2009-02-12" "2006-11-12" NA "2007-06-30" NA # [6] NA "2006-01-22" "2005-09-24" "2012-02-15" NA ``` Any ideas on what to try next? Note that if I apply the same on the `dput`ed and copy/pasted character vector, everyth…

Accepted Answer

I could reproduce this on Windows 7 x64. There are many issues with how R and Windows interact with character encoding, and I don't pretend to understand them. In your case, simply converting to `latin1` encoding before converting to a `Date` should work.

```
as.Date(iconv(dates,from='UTF-8',to='latin1'),'%d. %B %Y')
#  [1] "2009-02-12" "2006-11-12" "2010-03-19" "2007-06-30" "2006-03-07" "2007-03-19"
#  [7] "2006-01-22" "2005-09-24" "2012-02-15" "2007-03-28"
```

There might be a way to get `as.Date` to recognize different encodings in Windows, but I don't know it.

as.Date yields NA for month name "März" (march)

Solution

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