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How to efficiently compare two unordered lists (not sets) in Python?
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For short lists, big-O analysis is usually irrelevant because the timings are dominated by constant factors. For the longer lists, I suspect something is wrong with your benchmarking. For 100 ints with 5 repeats each, I get: 127 usec for sorted and 42 for Count...
Hand Coded GUI Versus Qt Designer GUI [closed]
... compile into your application. We started using for that purpose but with all generated code, once you edit it, you can no longer go back and regenerate it without losing your edits. We ended up just taking the generated code and doing everything by hand henceforth.
Qt4
Qt4 has improved on Design...
How to change the ROOT application?
...tdown your Tomcat from the its bin directory (sh shutdown.sh). Then delete all the content of your Tomcat webapps folder (rm -fr *). Then rename your WAR file to ROOT.war, and finally start your Tomcat from the bin directory (sh startup.sh).
Leave your war file in $CATALINA_BASE/webapps under its or...
Why can outer Java classes access inner class private members?
...he inner class is just a way to cleanly separate some functionality that really belongs to the original outer class. They are intended to be used when you have 2 requirements:
Some piece of functionality in your outer class would be most clear if it was implemented in a separate class.
Even thoug...
Is there any Rails function to check if a partial exists?
..., I'm using the following in my Rails 3/3.1 projects:
lookup_context.find_all('posts/_form').any?
The advantage over other solutions I've seen is that this will look in all view paths instead of just your rails root. This is important to me as I have a lot of rails engines.
This also works in R...
What's the difference between ConcurrentHashMap and Collections.synchronizedMap(Map)?
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For your needs, use ConcurrentHashMap. It allows concurrent modification of the Map from several threads without the need to block them. Collections.synchronizedMap(map) creates a blocking Map which will degrade performance, albeit ensure consistency (if used properl...
How do I upgrade my ruby 1.9.2-p0 to the latest patch level using rvm?
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First of all, update your RVM installation by running rvm get stable.
To make sure you're running the new RVM version, you'll then need to run rvm reload (or just open a new terminal).
Once that's done, you can ask RVM to list the r...
javax.faces.application.ViewExpiredException: View could not be restored
...ession cookie is not maintained anymore for some reason in browser, or by calling HttpSession#invalidate() in server, or due a server specific bug with session cookies as known in WildFly), then the serialized view state is not available anymore in the session and the enduser will get this exception...
knitr Markdown highlighting in Emacs?
...r the former you need polymode and for the latter markdown.el. Besides, if all you want is to just switch the ESS engine from Sweave to knitr (without highlighting!), there is no need to go through all the complication of this article, just add (setq ess-swv-processor 'knitr) in you init file.
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Is there a setting on Google Analytics to suppress use of cookies for users who have not yet given c
... implement a mechanism where, on first visit, Google Analytics is automatically disabled in the absence of an opt-in cookie (cookies that determine cookie preferences are explicitly allowed), and then, if an opt-in happens, re-runs Google Analytics. On subsequent pageviews, all would run smoothly.
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