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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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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.
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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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Reflection: How to Invoke Method with parameters
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Change "methodInfo" to "classInstance", just like in the call with the null parameter array.
result = methodInfo.Invoke(classInstance, parametersArray);
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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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Vim: How to insert in visual block mode?
...capital I.
Lowercase i will not work.
Then type the things you want and finally to apply it to all lines, press Esc twice.
If this doesn't work...
Check if you have +visualextra enabled in your version of Vim.
You can do this by typing in :ver and scrolling through the list of features. (You migh...
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...
Why is spawning threads in Java EE container discouraged?
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It is discouraged because all resources within the environment are meant to be managed, and potentially monitored, by the server. Also, much of the context in which a thread is being used is typically attached to the thread of execution itself. If y...