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How to get all subsets of a set? (powerset)
... the letters to form strings) writing a custom recipe utilizing generators and building up the output you want (e.g. adding together two strings) can be much faster.
– Ceasar Bautista
Feb 23 '18 at 7:48
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Is there a Boolean data type in Microsoft SQL Server like there is in MySQL? [duplicate]
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Also, It is standard practice for 0 to be construed as FALSE, 1 to be construed as TRUE and Nulls, when allowed, would be reflected as NULL.
– reido113
Jan 29 '13 at 20:36
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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...
Delete multiple records using REST
...things that don't make sense from your point of view.
This choice is best, and can be done RESTfully. If you are creating an API and you want to allow mass changes to resources, you can use REST to do it, but exactly how is not immediately obvious to many. One method is to create a ‘change request...
What does O(log n) mean exactly?
I am learning about Big O Notation running times and amortized times. I understand the notion of O(n) linear time, meaning that the size of the input affects the growth of the algorithm proportionally...and the same goes for, for example, quadratic time O(n2) etc..even algorithms, such as permu...
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 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 ...
How to convert a data frame column to numeric type?
... 3
4 d 4 4 d 4
5 e 5 5 e 5
and let us run:
> sapply(d, mode)
char fake_char fac char_fac num
"character" "character" "numeric" "numeric" "numeric"
> sapply(d, class)
char fake_char fac char...
Looping in a spiral
...algorithm that would let him loop through the elements of an NxM matrix (N and M are odd). I came up with a solution, but I wanted to see if my fellow SO'ers could come up with a better solution.
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