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Group by multiple columns in dplyr, using string vector input
I'm trying to transfer my understanding of plyr into dplyr, but I can't figure out how to group by multiple columns.
9 Answ...
Objective-C declared @property attributes (nonatomic, copy, strong, weak)
...ail when I must use each attribute: nonatomic , copy , strong , weak , and so on, for a declared property, and explain what each does? Some sort of example would be great also. I am using ARC.
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How to change border color of textarea on :focus
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I think better is using outline and shadow together "outline: solid 2px #8dc63f; box-shadow: 0 0 21px #8dc63f;" :-)
– BG BRUNO
Jun 8 '17 at 21:04
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nServiceBus vs Mass Transit vs Rhino Service Bus vs other?
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I'd recommend staying away from hand-rolled solutions as there is a bunch of somewhat difficult stuff that needs to be gotten just right - like how transactions are handled, how exceptions cause rollbacks, how to stop rolling back endlessly (poison messages)...
Can you list the keyword arguments a function receives?
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A little nicer than inspecting the code object directly and working out the variables is to use the inspect module.
>>> import inspect
>>> def func(a,b,c=42, *args, **kwargs): pass
>>> inspect.getargspec(func)
(['a', 'b', 'c'], 'args', 'kwargs', (42,))
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Is String.Format as efficient as StringBuilder
...would run more quickly using .Append(). But it's a guess, try benchmarking and/or profiling the two to get a proper comparison.
This chap, Jerry Dixon, did some benchmarking:
http://jdixon.dotnetdevelopersjournal.com/string_concatenation_stringbuilder_and_stringformat.htm
Updated:
Sadly the ...
How to prevent errno 32 broken pipe?
... client program doesn't wait till all the data from the server is received and simply closes a socket (using close function).
In a C program you would normally try setting to ignore SIGPIPE signal or setting a dummy signal handler for it. In this case a simple error will be returned when writing t...
How can I find the latitude and longitude from address?
...s the "java.io.IOException service not available"
– Kandha
Aug 26 '10 at 13:02
3
You need the rig...
How do you specify the Java compiler version in a pom.xml file?
...compile it on netbeans, everything is fine, but if I want to run it on command line, I will get these errors:
5 Answers
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How to read the Stock CPU Usage data
On Ice Cream Sandwich, an option in the Developer Options is "Show CPU Usage", which adds an overlay on the screen (see screenshot below).
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