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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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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...
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...
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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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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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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From inside of a Docker container, how do I connect to the localhost of the machine?
...nnect to the MySql from within my Nginx. The MySql is running on localhost and not exposing a port to the outside world, so its bound on localhost, not bound on the ip address of the machine.
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What is the maximum length of latitude and longitude? [closed]
How long can latitude and longitude be?
7 Answers
7
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What is the best Java email address validation method? [closed]
...verification email to the address if you want to ensure it's a real email, and that the owner wants it used on your site.
EDIT: There was a bug where it was too restrictive on domain, causing it to not accept valid emails from new TLDs.
This bug was resolved on 03/Jan/15 02:48 in commons-validator ...