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Do I need to disable NSLog before release Application?
...xcode it write to stderr too.
The main problem lays in the first one. In order to achieve thread safe, every time NSLog is called, it opens an connection to ASL facility, sends message, and closes the connection. The connection operation is very expensive. Another reason is that NSLog spends some ...
Why prefer two's complement over sign-and-magnitude for signed numbers?
I'm just curious if there's a reason why in order to represent -1 in binary, two's complement is used: flipping the bits and adding 1?
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Split Python Flask app into multiple files
...consider using different URL prefixes for the different APIs/Blueprints in order to cleanly separate them. This can be done with a slight modification to the above register_blueprint call:
app.register_blueprint(account_api, url_prefix='/accounts')
For further documentation, you may also have a l...
Encoding an image file with base64
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(Incidentally, answer order cannot be relied on here, so it is worth avoiding comments like "the first answer". The one that appears first may change over time.:-))
– halfer
Apr 26 '19 at 21:27
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Grid of responsive squares
...his is great. Just a heads-up for others: if you're using * { box-sizing: border-box; } you'll need to adjust the height and width in the .content div to 100%. :)
– Rob Flaherty
Oct 3 '14 at 2:46
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Is there any difference between the `:key => “value”` and `key: “value”` hash notations?
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Both Perl and PHP use =>. I'd guess that Ruby, being heavily inspired by Perl, borrowed the syntax from Perl :)
– Daniel Serodio
Aug 7 '17 at 19:19
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Python argparse: How to insert newline in the help text?
... the right direction above. But that solution needs slight modification in order to format description section.
Anyway, custom formatter is needed. I extended existing HelpFormatter class and overrode _fill_text method like this:
import textwrap as _textwrap
class MultilineFormatter(argparse.HelpF...
Converting strings to floats in a DataFrame
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What are the differences between vector and list data types in R?
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As someone who's just gotten into R, but comes from a C/Java/Ruby/PHP/Python background, here's how I think of it.
A list is really an array + a hashmap. It's a PHP associative array.
> foo = list(bar='baz')
> foo[1]
'baz'
> foo$bar
'baz'
> foo[['bar']]
'baz'
A vector is a f...
In Python, using argparse, allow only positive integers
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