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How to select a CRAN mirror in R
I'm trying to install a package through the R prompt by doing the following:
11 Answers
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Lua string to int
...t'll convert "10" to integer and then add 0 to it. (The lack of clarity is all the more reason to use tonumber instead, though!)
– Rena
Jun 28 '15 at 6:32
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Error handling with node.js streams
...ansform
Transform streams are both readable and writeable, and thus are really good 'middle' streams. For this reason, they are sometimes referred to as through streams. They are similar to a duplex stream in this way, except they provide a nice interface to manipulate the data rather than just sen...
Adding a column to a data.frame
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@RomanLuštrik, This solution can be rewritten really nicely in a single line. Using your your.df data, you can simply do your.df$group = cumsum(your.df[, 1]==1) to get your new group column.
– A5C1D2H2I1M1N2O1R2T1
Apr 16 '12 at 17:47
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Python - Count elements in list [duplicate]
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len(myList) should do it.
len works with all the collections, and strings too.
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WARN Could not determine content-length of response body. Set content-length of the response or set
I just upgraded to rails 3.2.2, and now on rails s, page load, I get all these errors in the log:
3 Answers
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require file as string
...ondering how I can import any file as a string. Lets say I have a txt file all I want is to load it into a variable as such.
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UITextView style is being reset after setting text property
I have UITextView *_masterText and after call method setText property font is being reset.
It's happening after I change sdk 7.
_masterText is IBOutlet , global and properties are set in storyboard. It's only me or this is general SDK bug?
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Retrieving the last record in each group - MySQL
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MySQL 8.0 now supports windowing functions, like almost all popular SQL implementations. With this standard syntax, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m...
time.sleep — sleeps thread or process?
...look in Modules/timemodule.c in the Python source, you'll see that in the call to floatsleep(), the substantive part of the sleep operation is wrapped in a Py_BEGIN_ALLOW_THREADS and Py_END_ALLOW_THREADS block, allowing other threads to continue to execute while the current one sleeps. You can also...