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Reshaping data.frame from wide to long format
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reshape() takes a while to get used to, just as melt/cast. Here is a solution with reshape, assuming your data frame is called d:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
...
SQL WHERE.. IN clause multiple columns
...te that if your columns are numeric, some SQL dialects will require you to cast them to strings first. I believe SQL server will do this automatically.
To wrap things up: As usual there are many ways to do this in SQL, using safe choices will avoid suprises and save you time and headaces in the l...
What are the differences between PMD and FindBugs?
...method may return null, reference comparison of Boolean values, impossible cast, 32bit int shifted by an amount not in the range of 0-31, a collection which contains itself, equals method always returns true, an infinite loop, etc.
Usually each of them finds a different set of problems. Use both. T...
NSOperation vs Grand Central Dispatch
...programming for iOS. So far I've read about NSOperation/NSOperationQueue and GCD . What are the reasons for using NSOperationQueue over GCD and vice versa?
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how to get program files x86 env variable?
... like to know how I can display the location of Program Files (x86) in command prompt. I'm using Windows 7 64bit.
4 Answer...
C# difference between == and Equals()
... comparisons should only be performed IMHO with values that are explicitly cast to matching types. The comparison of a float to something other than a float, or a double to something other than a double, strikes me as a major code smell that should not compile without diagnostics.
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How can I replace a newline (\n) using sed?
...w can I replace a newline (" \n ") with a space (" ") using the sed command?
42 Answers
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How do I use CSS in Django?
I am creating my application using Django, and am wondering how I can make Django use my CSS file? What settings do I need to do to make Django see the css file?
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Dark theme in Netbeans 7 or 8
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Darcula
UPDATE 2016-02: NetBeans 8 now has a Darcula plugin, better and more complete than the alternatives discussed in old version of this Answer.
The attractive and productive Darcula theme in JetBrains IntelliJ is now available in NetBeans 8.0 & 8.1!
The Real Thing
This plugin p...
How to execute a java .class from the command line
...classpath ( where java looks for .class definitions )
If that's the case and listing the contents of your dir displays:
Echo.java
Echo.class
Then any of this may work:
java -cp . Echo "hello"
or
SET CLASSPATH=%CLASSPATH;.
java Echo "hello"
And later as Fredrik points out you'll get an...