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if A vs if A is not None:

... method returns None if there were no rows in the result. Suppose you were selecting a value that might return 0 and need to know whether it's actually 0 or whether the query had no results at all. A common idiom is to give a function or method's optional argument the default value of None, and the...
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Android Studio Project Structure (v.s. Eclipse Project Structure)

... For android Studio 3.0.1 and selected all features: Android O latest Android Auto Android things Android wear Android TV C++ support Kotlin support The structure in version 3.0.1 does not look at all like all other answers. Recent structure is as di...
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How do I clone a github project to run locally?

...md\ In windows 7: Right-click "Computer" on the Desktop or Start Menu. Select "Properties". On the very far left, click the "Advanced system settings" link. Click the "Environment Variables" button at the bottom. Double-click the "Path" entry under "System variables". At the end of "Variable val...
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Css pseudo classes input:not(disabled)not:[type=“submit”]:focus

...and you seem to have mixed up/missing colons and parentheses on the :not() selector. Demo: http://jsfiddle.net/HSKPx/ One thing to note: I may be wrong, but I don't think disabled inputs can normally receive focus, so that part may be redundant. Alternatively, use :enabled input:enabled:not([typ...
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Is there ever a time where using a database 1:1 relationship makes sense?

...re is a larger set of data that needs to be collected, if and only if they select to have health coverage. I would keep the demographic data regarding health coverage in a different table to both give easier security partitioning and to avoid hauling that data around in queries unrelated to insuranc...
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Peak signal detection in realtime timeseries data

...lter(i) to std(filteredY(i-lag),...,filteredY(i)); end Rules of thumb for selecting good parameters for your data can be found below. Demo The Matlab code for this demo can be found here. To use the demo, simply run it and create a time series yourself by clicking on the upper chart. The algorith...
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Hover and Active only when not disabled

... There's also the :not() selector, but then again, it's only supported since IE9 as well. See: developer.mozilla.org/en-US/docs/Web/CSS/:not – jnns Nov 28 '13 at 16:26 ...
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Fluid width with equally spaced DIVs

...g .box1, .box2, .box3, .box4 { ... to #container > div { ... This selects any div that is the first child of the #container div, and no others below it. To generalize the background colors, you can use the CSS3 nth-order selector, although it's only supported in IE9+ and other modern browse...
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Git: show more context when using git add -i or git add -e?

I'm selectively committing parts of a large file and I'd like to see more context around each hunk. Is this possible? 2 Ans...
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What is the difference between the Eclipse Package Explorer and the Eclipse Project Explorer?

...kage Explorer is it is the only explorer that appears in the list when you select "Show In" on a file that is being edited or has been found in the Search view. share | improve this answer ...