Question

有没有办法找出引入了哪些版本的R某些功能？例如，regmatches是一个有用的函数，但它是相当新的，我相信它是在2.14中引入的。我怎么能轻易找出R 2.14中引入的regmatches之类的东西？

Answer 1

比Dirk的解决方案更容易使用R的news函数：

> newsDB <- news()
> news(grepl("regmatches",Text), db=newsDB)
Changes in version 2.14.0:

NEW FEATURES

    o   New function regmatches() for extracting or replacing matched or
         non-matched substrings from match data obtained by regexpr(),
         gregexpr() and regexec().

从R-3.3.0开始，news将通过HTML帮助系统启动（如果可用）。您可以通过print.news_db方法禁止它：

> print(news(grepl("news",Text), db=newsDB), doBrowse=FALSE)
Changes in version 3.3.0:

NEW FEATURES

    o   news() now displays R and package news files within the HTML help
         system if it is available.  If no news file is found, a visible
         NULL is returned to the console.

Answer 2

您可以使用SVN存储库：

edd@max:~/svn/r-devel/src/library/base/man$ svn log regmatches.Rd 
------------------------------------------------------------------------
r57006 | hornik | 2011-09-14 14:04:21 -0500 (Wed, 14 Sep 2011) | 1 line

Improve example.
------------------------------------------------------------------------
r56997 | hornik | 2011-09-12 15:16:03 -0500 (Mon, 12 Sep 2011) | 1 line

Document regmatches replacement function.
------------------------------------------------------------------------
r56893 | hornik | 2011-09-02 05:31:01 -0500 (Fri, 02 Sep 2011) | 1 line

Add first version of regmatches replacement function.
------------------------------------------------------------------------
r56818 | hornik | 2011-08-29 02:49:17 -0500 (Mon, 29 Aug 2011) | 1 line

Spelling.
------------------------------------------------------------------------
r56752 | hornik | 2011-08-18 01:40:07 -0500 (Thu, 18 Aug 2011) | 1 line

Add regmatches().
------------------------------------------------------------------------
edd@max:~/svn/r-devel/src/library/base/man$

我将svn log应用到手册页，因为我没有立即看到定义函数的R文件;命令的工作方式与...相同......

弄清楚引入了什么版本的R函数

2 个答案: