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What is the purpose of setting a key in data.table?
... updated this answer again (Feb 2016) in light of the new on= feature that allows ad-hoc joins as well. See history for earlier (outdated) answers.
What exactly does setkey(DT, a, b) do?
It does two things:
reorders the rows of the data.table DT by the column(s) provided (a, b) by reference, a...
Writing a Python list of lists to a csv file
...It kinda makes sense in hindsight, but not informative of where to look at all.
– Rambatino
May 25 '18 at 7:30
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Generating matplotlib graphs without a running X server [duplicate]
...variable which means a running X server. Some web hosting services do not allow a running X server session. Is there a way to generate graphs using matplotlib without a running X server?
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How to delete an SMS from the inbox in Android programmatically?
... onReceive() method, before performing anything with your message, simply call abortBroadcast();
EDIT: As of KitKat, this doesn't work anymore apparently.
EDIT2: More info on how to do it on KitKat here:
Delete SMS from android on 4.4.4 (Affected rows = 0(Zero), after deleted)
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Unit testing private methods in C#
Visual Studio allows unit testing of private methods via an automatically generated accessor class. I have written a test of a private method that compiles successfully, but it fails at runtime. A fairly minimal version of the code and the test is:
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multiple packages in context:component-scan, spring config
...lsorily need to add specific packages or it can scan sub packages automatically if we only define the top level package?
– Nikhil Sahu
Jun 17 '16 at 13:52
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How to convert currentTimeMillis to a date in Java?
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Calendar objects are generally considered quite large, so should be avoided when possible. A Date object is going to be better assuming it has the functionality you need. "Date date=new Date(millis);" provided in the other answer by user AVD is going ...
Difference between toFixed() and toPrecision()?
...om Mozilla Doc Center for toFixed() and for toPrecision(). Fortunately for all of us, MDC and w3schools agree with each other in this case.
For completeness, I should mention that toFixed() is equivalent to toFixed(0) and toPrecision() just returns the original number with no formatting.
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How exactly does tail recursion work?
...nt one but without explicit recursion (that is, without explicit function calls). If you change the logic into something non-equivalent, you may indeed make the function loop forever in some or all cases.
– Alexey Frunze
Mar 20 '13 at 9:30
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How to find what code is run by a button or element in Chrome using Developer Tools
...ess the F11 key (Step In) until desired source code appears
Source code finally reached
In the jsFiddle sample provided above, I had to press F11 108 times before reaching the desired event handler/function
Your mileage may vary, depending on the version of jQuery (or framework library) used to bi...