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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
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If you're actually dealing with 1-dimensional arrays (like in you're example) then on you're first line use a Series instead of a DataFrame, like @DSM used: df = pd.Series({'countries':['US','UK','Germany','China']})
–...
What's the best strategy for unit-testing database-driven applications?
...ns that are driven by databases of varying complexity on the backend. Typically, there's an ORM layer separate from the business and presentation logic. This makes unit-testing the business logic fairly straightforward; things can be implemented in discrete modules and any data needed for the test...
What is a Context Free Grammar?
...y and then the Wikipedia entry on formal grammar, I am left utterly and totally befuddled. Would someone be so kind as to explain what these things are?
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How to design a database for User Defined Fields?
...rformance is the primary concern, I would go with #6... a table per UDF (really, this is a variant of #2). This answer is specifically tailored to this situation and the description of the data distribution and access patterns described.
Pros:
Because you indicate that some UDFs
have values for a...
Why is Spring's ApplicationContext.getBean considered bad?
...g question: Auto-cast Spring Beans and had multiple people respond that calling Spring's ApplicationContext.getBean() should be avoided as much as possible. Why is that?
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Eclipse / Android : “Errors running builder 'Android Pre Compiler' on project…”
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For those of you who don't want to install preview version of ADT, there is a workaround described here.
Open properties of project in Eclipse then Resources -> Resource filters.
Click the "Add..." button -> Check "Exclude all", "Files and folders",...
Can I safely delete contents of Xcode Derived data folder?
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Yes, you can delete all files from DerivedData sub-folder (Not DerivedData Folder) directly.
That will not affect your project work. Contents of DerivedData folder is generated during the build time and you can delete them if you want. It's no...
HTML 5 Favicon - Support?
.../to/favicon.png">
This icon should be 196x196 pixels in size to cover all devices that may use this icon.
To cover touch icons on mobile devices we are going to use Apple's proprietary way to cite a touch icon:
<link rel="apple-touch-icon-precomposed" href="apple-touch-icon-precomposed.pn...
What is the difference between NULL, '\0' and 0?
...0 has different meanings depending upon the context in which it's used. In all cases, it is still an integer constant with the value 0, it is just described in different ways.
If a pointer is being compared to the constant literal 0, then this is a check to see if the pointer is a null pointer. Thi...
iOS 6 apps - how to deal with iPhone 5 screen size? [duplicate]
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All apps will continue to work in the vertically stretched screen from what I could tell in today's presentation. They will be letterboxed or basically the extra 88 points in height would simply be black.
If you only plan to...