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Transpose a data frame
...You'd better not transpose the data.frame while the name column is in it - all numeric values will then be turned into strings!
Here's a solution that keeps numbers as numbers:
# first remember the names
n <- df.aree$name
# transpose all but the first column (name)
df.aree <- as.data.frame(...
How do I change the background color of a plot made with ggplot2
...s the theme_bw, giving you a white background and grey gridlines. I use it all the time, as in print it looks much better than the default grey background: myplot + theme_bw()
– ROLO
Dec 16 '11 at 9:11
...
Abstract classes in Swift Language
... importantly, notice that there is no dynamic dispatch. When logSalary is called on the instance that is stored as a SoftwareEngineer it calls the overridden version of the method. When logSalary is called on the instance after it has been cast to an Employee, it calls the original implementation (i...
XPath: select text node
...t or
the second text node via XPath?
Use:
/node/text()
This selects all text-node children of the top element (named "node") of the XML document.
/node/text()[1]
This selects the first text-node child of the top element (named "node") of the XML document.
/node/text()[2]
This selects th...
Why does Python print unicode characters when the default encoding is ASCII?
...ng the encoding scheme currently stored in sys.stdout.encoding. Python actually picks up this setting from the environment it's been initiated from. If it can't find a proper encoding from the environment, only then does it revert to its default, ASCII.
For example, I use a bash shell which encodin...
Is it possible to set a number to NaN or infinity?
...question over a second time!! Sorry! That said, it wouldn't hurt to say so all the same because it's an easy trap to fall into, NaN != NaN
– David Heffernan
Mar 25 '11 at 22:30
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What is Microsoft.csharp.dll in .NET 4.0
... The assembly contains the C# runtime binder.
The C# compiler has essentially been extracted out into a library so that it can emit, compile and run code needed to support the dynamic keyword. The first time you use dynamic in your code, this assembly (as well as System.dll, System.Core.dll and Sy...
split string only on first instance of specified character
...Very elegant. Works like a charm. Thank you.
– Ofeargall
Jan 5 '11 at 18:43
12
Just to be clear, ...
@OneToMany List vs Set difference
...of addresses, you won't be able to use a single query to load persons with all their contacts and all their addresses. The solution in this case is to make two queries (which avoids the cartesian product), or to use a Set instead of a List for at least one of the collections.
It's often hard to use...
How to determine the version of the C++ standard used by the compiler?
...
By my knowledge there is no overall way to do this. If you look at the headers of cross platform/multiple compiler supporting libraries you'll always find a lot of defines that use compiler specific constructs to determine such things:
/*Define Microsoft V...