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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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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...
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 ...
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...
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...
Benchmarking (python vs. c++ using BLAS) and (numpy)
I would like to write a program that makes extensive use of BLAS and LAPACK linear algebra functionalities. Since performance is an issue I did some benchmarking and would like know, if the approach I took is legitimate.
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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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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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Type-juggling and (strict) greater/lesser-than comparisons in PHP
PHP is famous for its type-juggling. I must admit it puzzles me, and I'm having a hard time to find out basic logical/fundamental things in comparisons.
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