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Check whether number is even or odd
...r. Obviously if the first bit is set, then the number must be odd. It's usually faster, and it reads just as well in my opinion. I think the reason others don't prefer it over modulus comes down to a lack of understanding of binary.
– crush
Feb 13 '14 at 21:47
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Can you autoplay HTML5 videos on the iPad?
...ugh both script and attribute implementations.
In Safari, on iOS (for all devices, including iPad), where the user may be on a cellular network and be charged per data unit, preload and
auto-play are disabled. No data is loaded until the user initiates it." - Apple documentation.
Here is a ...
How do I set default values for functions parameters in Matlab?
...n, nargchk, etc. They're useful functions for this sort of thing. varargs allow you to leave a variable number of final arguments, but this doesn't get you around the problem of default values for some/all of them.
share
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bundler vs RVM vs gems vs RubyGems vs gemsets vs system ruby [closed]
...encies. Rubygems is the name of the package manager - the tool used to install the packages (while the gems are the packages themselves). Rubygems is now part of Ruby.
Bundler is what makes managing gems bearable. Based on your Gemfile, a simple call to bundler using bundle install will download an...
Status bar won't disappear
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How to do this globally?
– jjxtra
Aug 25 '13 at 19:44
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How to debug Google Apps Script (aka where does Logger.log log to?)
...to log to Stackdriver.
Logger.log will either send you an email (eventually) of errors that have happened in your scripts, or, if you are running things from the Script Editor, you can view the log from the last run function by going to View->Logs (still in script editor). Again, that will on...
Is it possible to disable the network in iOS Simulator?
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Network Link Conditioner allows you to specify a percentage of packets to be dropped, but as far as I've seen there's unfortunately no way to disable all connectivity.
– modocache
Apr 9 '12 at 8:57
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Set up a scheduled job?
...Django, and I'm curious if there is a way to schedule a job to run periodically.
24 Answers
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Counting null and non-null values in a single query
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If I understood correctly you want to count all NULL and all NOT NULL in a column...
If that is correct:
SELECT count(*) FROM us WHERE a IS NULL
UNION ALL
SELECT count(*) FROM us WHERE a IS NOT NULL
Edited to have the full query, after reading the comments :]
S...
What killed my process and why?
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I just wrote a program that malloc'd memory in an inifite loop. After the system got slow, "Killed" was displayed in the terminal and the process was terminated. The file /var/log/kern.log contained a lot of info about the termination. -Thanks for the...