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How to Correctly Use Lists in R?

... Just to address the last part of your question, since that really points out the difference between a list and vector in R: Why do these two expressions not return the same result? x = list(1, 2, 3, 4); x2 = list(1:4) A list can contain any other class as each element. So you can ha...
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Check if database exists in PostgreSQL using shell

...s (4 rows) Using the naive approach means that searching for a database called "List, "Access" or "rows" will succeed. So we pipe this output through a bunch of built-in command line tools to only search in the first column. The -t flag removes headers and footers: my_db | my_user | UTF...
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What's the Point of Multiple Redis Databases?

...ce are no different than schemas in RDBMS database instances. So, with all of that said, why/when would I ever want to use multiple Redis databases instead of just spinning up an extra instance of Redis for each extra database I want? There's one clear advantage of using redis databases in...
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Why is “if not someobj:” better than “if someobj == None:” in Python?

...a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero. Otherwise, if the object has a __len__ special method (as do container built-ins, li...
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Undo a git stash

...ll not reset what is in the staging directory, so you will have to restage all that (which can be annoying if you had just done a complex git add -p – Nick Jan 2 '13 at 17:31 ...
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Could not load type 'System.Runtime.CompilerServices.ExtensionAttribute' from assembly 'mscorlib

...ilerServices.ExtensionAttribute' from assembly mscorlib Yes, this technically can go wrong when you execute code on .NET 4.0 instead of .NET 4.5. The attribute was moved from System.Core.dll to mscorlib.dll in .NET 4.5. While that sounds like a rather nasty breaking change in a framework version...
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For a boolean field, what is the naming convention for its getter/setter?

...e section of Sun's code conventions where boolean getter names are specifically covered? I could not find it. – Konstantin Pelepelin Mar 29 '17 at 17:36 4 ...
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How to create .pfx file from certificate and private key?

I need .pfx file to install https on website on IIS. 15 Answers 15 ...
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Does Django scale? [closed]

...erformance. That would be 432,000 hits per hour. Response times aren't small (our transactions are large) but there's no degradation from our baseline performance as the load increases. We're using Apache front-ending Django and MySQL. The OS is Red Hat Enterprise Linux (RHEL). 64-bit. We use ...
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How to find available versions for a bower dependency

... command to get detailed info specific to a package. bower search prints all packages that has the query string as a substring. – Yiling Aug 29 '15 at 16:15 ...