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How to wait for a keypress in R?
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As someone already wrote in a comment, you don't have to use the cat before readline(). Simply write:
readline(prompt="Press [enter] to continue")
If you don't want to assign it to a variable and don't want a return printed in the console, wrap the readline() in an invisible():
invisib...
How are feature_importances in RandomForestClassifier determined?
I have a classification task with a time-series as the data input, where each attribute (n=23) represents a specific point in time. Besides the absolute classification result I would like to find out, which attributes/dates contribute to the result to what extent. Therefore I am just using the feat...
Preserving order with LINQ
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I examined the methods of System.Linq.Enumerable, discarding any that returned non-IEnumerable results. I checked the remarks of each to determine how the order of the result would differ from order of the source.
Preserves Order Absolutely. You can map a source element by i...
What's the magic of “-” (a dash) in command-line parameters?
...cify standard input or output rather than an actual file name.
That's the case for your first and third example. For example, the cdrecord command is taking standard input (the ISO image stream produced by mkisofs) and writing it directly to /dev/dvdrw.
With the cd command, every time you change ...
Why can't I call read() twice on an open file?
...ontents of a given file twice using the read() method. Strangely, when I call it the second time, it doesn't seem to return the file content as a string?
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Why can I pass 1 as a short, but not the int variable i?
...hy does the first and second Write work but not the last? Is there a way I can allow all 3 of them and detect if it was 1, (int)1 or i passed in? And really why is one allowed but the last? The second being allowed but not the last really blows my mind.
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Get class that defined method
How can I get the class that defined a method in Python?
6 Answers
6
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Does Swift support reflection?
...confirmed the reflect() function exists to support the Playground. But you can still have some fun with it :) here i've hacked out a little model serializer using it. Paste it into the Playground and have fun: gist.github.com/mchambers/67640d9c3e2bcffbb1e2
– Marc Chambers
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How to check if command line tools is installed
...ith OS X 10.8.2.
XCode is installed. I know this as it appears in the Applications directory.
There are also the xcodebuild and xcode-select files in /usr/bin
I need to know if the command line tools is installed.
Is there a command for it?
What can I do to see if XCode CLT is installed and if yes t...
Entity Framework 4 Single() vs First() vs FirstOrDefault()
...- when you want to get an item by primary key. This will return null if it can't find an item. It will look in the context before going to the database (as pointed out by Yaron in the comments) which can be an important efficiency factor if you need to get the same entity multiple times while the sa...