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Drop unused factor levels in a subsetted data frame
...t, so the mydf <- droplevels(mydf) solution suggested by Roman Luštrik and Tommy O'Dell below is preferable.
– Johan
May 9 '14 at 10:41
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How do I trim whitespace from a string?
How do I remove leading and trailing whitespace from a string in Python?
12 Answers
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Adding a Google Plus (one or share) link to an email newsletter
... a share/+1 link for Google+ in a Newsletter, much like the Facebook share and tweeter tweet links can be embedded in a newsletter, which can be achieved with the following two urls:
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iphone/ipad: How exactly use NSAttributedString?
Yes, many people are saying about Rich Text in iPhone/iPad and many knows about NSAttributedString .
9 Answers
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.NET: Simplest way to send POST with data and read response
...rol over the HTTP headers, you could attempt the same using HttpWebRequest and reference RFC2616 (w3.org/Protocols/rfc2616/rfc2616.txt). Answers from jball and BFree follow that attempt.
– Chris Hutchinson
Nov 3 '10 at 15:30
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What are “signed” cookies in connect/expressjs?
...igure out what "signed cookies" actually are.
There isn't much on the net, and if I try this:
4 Answers
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What does the (unary) * operator do in this Ruby code?
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The * is the splat operator.
It expands an Array into a list of arguments, in this case a list of arguments to the Hash.[] method. (To be more precise, it expands any object that responds to to_ary/to_a, or to_a in Ruby 1.9.)
To illustrate, the following two ...
ZSH complains about RVM __rvm_cleanse_variables: function definition file not found
When using the latest ZSH and RVM on Mac OS X 10.7.4 ZSH complains about this:
5 Answers
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When should I use Memcache instead of Memcached?
It seems that PHP has two memcached libraries named memcache and memcached . What is the difference and how do you know which one to use? Is one outdated? It seems that memcached offers more methods so I would assume that means it has had the most development - but it also seems to require exter...
Searching for UUIDs in text with regex
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@cyber-monk: [0-9a-f] is identical to [a-f0-9] and [0123456789abcdef] in meaning and in speed, since the regex is turned into a state machine anyway, with each hex digit turned into an entry in a state-table. For an entry point into how this works, see en.wikipedia.org/wi...