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Convert a row of a data frame to vector
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Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
ADB Shell Input Events
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3 --> "KEYCODE_HOME"
4 --> "KEYCODE_BACK"
5 --> "KEYCODE_CALL"
6 --> "KEYCODE_ENDCALL"
7 --> "KEYCODE_0"
8 --> "KEYCODE_1"
9 --> "KEYCODE_2"
10 --> "KEYCODE_3"
11 --> "KEYCODE_4"
12 --> "KEYCODE_5"
13 --> "KEYCODE_6"
14 --> "KEYCODE_7"
1...
Checking a Python module version at runtime
...s have an attribute which holds the version information for the module (usually something like module.VERSION or module.__version__ ), however some do not.
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How to list out all the subviews in a uiviewcontroller in iOS?
I want to list out all the subviews in a UIViewController . I tried self.view.subviews , but not all of the subviews are listed out, for instance, the subviews in the UITableViewCell are not found. Any idea?
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LINQ Orderby Descending Query
...need to choose a Property to sort by and pass it as a lambda expression to OrderByDescending
like:
.OrderByDescending(x => x.Delivery.SubmissionDate);
Really, though the first version of your LINQ statement should work. Is t.Delivery.SubmissionDate actually populated with valid dates?
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How to count occurrences of a column value efficiently in SQL?
...Microsoft SQL (i.e 2000)
SELECT age, count(*)
FROM Students
GROUP by age
ORDER BY age
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Vim: insert the same characters across multiple lines
...e the screen in the first line - until Esc is pressed (6.), at which point all lines will be updated.
Press Esc.
An uppercase I must be used rather than a lowercase i, because the lowercase i is interpreted as the start of a text object, which is rather useful on its own, e.g. for selecting insi...
Allowed characters in Linux environment variable names
What characters are allowed in Linux environment variable names? My cursory search of man pages and the web did only produce information about how to work with variables, but not which names are allowed.
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How can I get the current screen orientation?
...lues ORIENTATION_PORTRAIT and ORIENTATION_LANDSCAPE. Is there a way to get all the four values from ActivityInfo? (That is LANDSCAPE_REVERSE and PORTRAIT_REVERSE as well)
– HRJ
May 4 '11 at 9:56
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Python argparse mutual exclusive group
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add_mutually_exclusive_group doesn't make an entire group mutually exclusive. It makes options within the group mutually exclusive.
What you're looking for is subcommands. Instead of prog [ -a xxxx | [-b yyy -c zzz]], you'd have:
p...