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How to check whether a pandas DataFrame is empty?
...[8]: len(df1.columns)
Out[8]: 0
In [9]: len(df2.columns)
Out[9]: 2
Critically, while the second dataframe df2 contains no data, it is not completely empty because it returns the amount of empty columns that persist.
Why it matters
Let's add a new column to these dataframes to understand the implic...
How to securely store access token and secret in Android?
...other apps cannot access them. On a rooted devices, if the user explicitly allows access to some app that is trying to read them, the app might be able to use them, but you cannot protect against that. As for encryption, you have to either require the user to enter the decrypt passphrase every time ...
HEAD and ORIG_HEAD in Git
..., and it is a commit on top of which "git commit" would make a new one. Usually HEAD is symbolic reference to some other named branch; this branch is currently checked out branch, or current branch. HEAD can also point directly to a commit; this state is called "detached HEAD", and can be understood...
What's the difference between window.location= and window.location.replace()?
...er won't be able to use the Back
button to navigate to it.
Oh and generally speaking:
window.location.href = url;
is favoured over:
window.location = url;
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Difference between MEAN.js and MEAN.io
... that there are two different stacks with either their own website and installation methods: mean.js and mean.io. So I came up asking myself this question: "Which one do I use?".
...
What are the relative strengths and weaknesses of Git, Mercurial, and Bazaar? [closed]
...ike that very much.
Bazaar is reasonably fast (very fast for trees with shallow history, but presently scales poorly with history length), and is easy-to-learn to those familiar with the command-line interfaces of traditional SCMs (CVS, SVN, etc). Win32 is considered a first-class target by its dev...
Create a custom View by inflating a layout?
...reate a Compound Control. You'll create a subclass of RelativeLayout, add all our your components in code (TextView, etc), and in your constructor you can read the attributes passed in from the XML. You can then pass that attribute to your title TextView.
http://developer.android.com/guide/topics...
Entity Framework and Connection Pooling
...tion Pooling (ADO.NET))
Never ever use global context. ObjectContext internally implements several patterns including Identity Map and Unit of Work. Impact of using global context is different per application type.
For web applications use single context per request. For web services use single con...
Using emit vs calling a signal as if it's a regular function in Qt
...e this:
#ifndef QT_NO_EMIT
# define emit
#endif
(The define guard is to allow you to use Qt with other frameworks that have colliding names via the no_keywords QMake config option.)
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How to retrieve form values from HTTPPOST, dictionary or?
...ld reflect the form input names and the default model binder will automatically create this object for you:
[HttpPost]
public ActionResult SubmitAction(SomeModel model)
{
var value1 = model.SimpleProp1;
var value2 = model.SimpleProp2;
var value3 = model.ComplexProp1.SimpleProp1;
......