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Count number of objects in list [closed]
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length(x)
Get or set the length of vectors (including lists) and factors, and of any other R object for which a method has been defined.
lengths(x)
Get the length of each element of a list or atomic vector (is.atomic) as an integer or numeric vector.
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Recursively add the entire folder to a repository
I am trying to add a branch to the master branch on GitHub and push a folder onto that branch.
15 Answers
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How to find server name of SQL Server Management Studio
...tance. To connect to it in Management Studio, just type . (dot) OR (local) and click Connect. If the instance name is different, then use .\[instance name] to connect to it (for example if the instance name is SQL2008, connect to .\SQL2008).
Also make sure SQL Server and SQL Server Browser services...
Scala Programming for Android
I have followed the tutorial at Scala and Android with Scala 2.7.3 final. The resulting Android App works but even the most basic application takes several minutes (!) to compile and needs 900 kb compressed, which is a show stopper for mobile applications. Additionally, the IDE runs out of mem...
How to “test” NoneType in python?
...ariable has None in it or not.
Quoting from is docs,
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object. x is not y yields the inverse truth value.
Since there can be only one instance of None, is would be the preferred way to check...
Is there a good charting library for iPhone? [closed]
I have a need to render and display charts (bar charts for now, but more types may be needed later) in an iPhone app I'm working on. I've done some looking around and it doesn't look like there are any really good, mature charting libraries for iPhone yet. I've also looked for something written for ...
Paste a multi-line Java String in Eclipse [duplicate]
...ter enabling the feature you still have to first write two quotation marks and then paste the text inside those marks.
– Lycha
Jul 29 '10 at 13:18
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'npm' is not recognized as internal or external command, operable program or batch file
...vironment Variables on the System Properties.
After that, reopen your command prompt and type
npm
This should work.
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How do I replace text inside a div element?
...t dynamically. What is the best, browser safe approach? I have prototypejs and scriptaculous available.
14 Answers
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Convert string to a variable name
...ttp://www.r-bloggers.com/converting-a-string-to-a-variable-name-on-the-fly-and-vice-versa-in-r/
To convert a string to a variable:
x <- 42
eval(parse(text = "x"))
[1] 42
And the opposite:
x <- 42
deparse(substitute(x))
[1] "x"
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