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Why use sprintf function in PHP?
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sprintf has all the formatting capabilities of the original printf which means you can do much more than just inserting variable values in strings.
For instance, specify number format (hex, decimal, octal), number of decimals, padding a...
How to reshape data from long to wide format
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The reshape comments and similar argument names aren't all that helpful. However, I have found that for long to wide, you need to provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide f...
Converting string from snake_case to CamelCase in Ruby
...equire "active_support/core_ext/string" is suffice, providing Rails is installed already.
– Masa Sakano
Jun 23 '18 at 2:03
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ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock'
I installed MySQL on Mac OS X Mountain Lion with homebrew install mysql , but when I tried mysql -u root I got the following error:
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Targeting .NET Framework 4.5 via Visual Studio 2010
Today I installed the .NET Framework 4.5 on my machine expecting to be able to use it from Visual Studio 2010, since it's just a minor update that should't pose problems for Visual Studio 2010. Unfortunately I am not, even manually removing certain 4.0 and adding the corresponding 4.5 assemblies r...
How to compile a static library in Linux?
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target: prerequisites - the rule head
$@ - means the target
$^ - means all prerequisites
$< - means just the first prerequisite
ar - a Linux tool to create, modify, and extract from archives see the man pages for further information. The options in this case mean:
r - replace files existing...
Best practices for in-app database migration for Sqlite
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I maintain an application that periodically needs to update a sqlite database and migrate old databases to the new schema and here's what I do:
For tracking the database version, I use the built in user-version variable that sqlite provides (sqlite does nothing w...
How to remove array element in mongodb?
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Is there call back with this?
– Oliver Dixon
Sep 1 '15 at 17:34
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What does Ruby have that Python doesn't, and vice versa?
There is a lot of discussions of Python vs Ruby, and I all find them completely unhelpful, because they all turn around why feature X sucks in language Y, or that claim language Y doesn't have X, although in fact it does. I also know exactly why I prefer Python, but that's also subjective, and would...
Getting Java version at runtime
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Wow, that kind of blew my mind. Though in my case, all I wanted was the first two parts of the version so: Runtime.class.getPackage().getSpecificationVersion()
– Wesley Hartford
Dec 10 '14 at 21:44
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