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Why does X[Y] join of data.tables not allow a full outer join, or a left join?
...f a philosophical question about data.table join syntax. I am finding more and more uses for data.tables, but still learning...
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How to Update Multiple Array Elements in mongodb
...1243
As a work around you can:
Update each item individually
(events.0.handled events.1.handled
...) or...
Read the document, do the edits
manually and save it replacing the
older one (check "Update if
Current" if you want to ensure
atomic updates)
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Is it safe to check floating point values for equality to 0?
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It is safe to expect that the comparison will return true if and only if the double variable has a value of exactly 0.0 (which in your original code snippet is, of course, the case). This is consistent with the semantics of the == operator. a == b means "a is equal to b".
It is not sa...
How to calculate time elapsed in bash script?
I print the start and end time using date +"%T" , which results in something like:
20 Answers
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Failed to Attach to Process ID Xcode
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Resetting the content and settings in the simulator worked for me. This is available in the "iOS Simulator" menu.
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Python str vs unicode types
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unicode is meant to handle text. Text is a sequence of code points which may be bigger than a single byte. Text can be encoded in a specific encoding to represent the text as raw bytes(e.g. utf-8, latin-1...).
Note that unicode is not encoded! T...
Regex for password must contain at least eight characters, at least one number and both lower and up
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Minimum eight characters, at least one letter and one number:
"^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8,}$"
Minimum eight characters, at least one letter, one number and one special character:
"^(?=.*[A-Za-z])(?=.*\d)(?=.*[@$!%*#?&])[A-Za-z\d@$!%*#?&]{8,}$"
Mini...
What does a tilde do when it precedes an expression?
I saw it in an answer, and I've never seen it before.
5 Answers
5
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Difference between exit(0) and exit(1) in Python
What's the difference between exit(0) and exit(1) in Python?
5 Answers
5
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When to use lambda, when to use Proc.new?
In Ruby 1.8, there are subtle differences between proc/lambda on the one hand, and Proc.new on the other.
14 Answers
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