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How to check whether a pandas DataFrame is empty?
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This seems like a shame, since you need to know that df is a pd.DataFrame. I'd like to know the motivation for not implementing bool() on pd.DataFrame.
– Quant
Feb 14 '14 at 16:55
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How to determine if a number is a prime with regex?
...ce again the returning of the negation of the match result.
Do you see it now? It's unbelievably tricky (and computationally expensive!) but it's also kind of simple at the same time, once you get it. :-)
I can elaborate if you have further questions, like on how regex parsing actually works. But ...
Gridview with two columns and auto resized images
...white"
android:background="#55000000"/>
</FrameLayout>
Now make some sort of adapter for your GridView:
src/com/example/graphicstest/MyAdapter.java
private final class MyAdapter extends BaseAdapter {
private final List<Item> mItems = new ArrayList<Item>();
p...
In JavaScript, does it make a difference if I call a function with parentheses?
...they can be passed around exactly as if we were passing around values.
So now to the difference of assignment:
var operator = 3;
var operand = 4;
var ret = Multiply(operator, operand);
At the point of defining the ret variable, Multiply is executed and the return value is assigned - ret becomes ...
What is the difference between properties and attributes in HTML?
...ibute value. type isn't a pure reflected property because it's limited to known values (e.g., the valid types of an input). If you had <input type="foo">, then theInput.getAttribute("type") gives you "foo" but theInput.type gives you "text".
In contrast, the value property doesn't reflect the ...
What are the new documentation commands available in Xcode 5? [closed]
...are.
- returns: The number squared.
*/
Notice how @param is now - parameter.
You can also now include bullets in your documentation:
/**
- square(5) = 25
- square(10) = 100
*/
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ITunes review URL and iOS 7 (ask user to rate our app) AppStore show a blank page
Does anybody knows if the technique used to ask the user to rate our app and open for him the App Store directly on the rating page is still working on iOS 7 ?
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Scala actors: receive vs react
...es something, a thread gets allocated to it, and it is initialized in it.
Now, the initialization part is important. A receiving thread is expected to return something, a reacting thread is not. So the previous stack state at the end of the last react can be, and is, wholly discarded. Not needing t...
Microsoft CDN for jQuery or Google CDN? [closed]
... What other factors could play a role in which cdn you decide to use? I know that Microsoft, Yahoo, and Google all have CDN's now.
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On delete cascade with doctrine2
...also want to point out that the way you have your cascade={"remove"} right now, if you delete a Child object, this cascade will remove the Parent object. Clearly not what you want.
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