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What is the difference between join and merge in Pandas?
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pandas.merge() is the underlying function used for all merge/join behavior.
DataFrames provide the pandas.DataFrame.merge() and pandas.DataFrame.join() methods as a convenient way to access the capabilities of pandas.merge(). For example, df1.merge(right=df2, ...) is equiva...
Why are empty strings returned in split() results?
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I was shocked to discover that curly quotes are actually valid in Python...but, but...how? The docs don't seem to mention this.
– Tim Pietzcker
Oct 8 '12 at 11:18
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Run certain code every n seconds [duplicate]
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This seems not to resolve the question at all... it does not repeat every second.
– Yan King Yin
Jul 5 '13 at 15:28
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Using the Android Application class to persist data
..., the Application class does not have the same life-cycle (i.e. it is, for all intents and purposes, always instantiated). Does it make sense to store the state information inside of the application class and then reference it from the Activity, or is that generally not the "acceptable" method due ...
How to set timer in android?
...up yet there are 3 simple ways to handle this.
Below is an example showing all 3 and at the bottom is an example showing just the method I believe is preferable. Also remember to clean up your tasks in onPause, saving state if necessary.
import java.util.Timer;
import java.util.TimerTask;
import...
What is an OS kernel ? How does it differ from an operating system? [closed]
...ernel is an operating system in that sense.
The end-user definition is usually something around "a software package that provides a desktop, shortcuts to applications, a web browser and a media player". A kernel doesn't match that definition.
So for an end-user a Linux distribution (say Ubuntu) is...
How to change the opacity (alpha, transparency) of an element in a canvas element after it has been
...;
Notes:
Set the 'src' last, to guarantee that your onload handler is called on all platforms, even if the image is already in the cache.
Wrap changes to stuff like globalAlpha between a save and restore (in fact use them lots), to make sure you don't clobber settings from elsewhere, particularl...
Immutable class?
...ot be changed after instantiation.
However, there must be care taken that all objects that are referenced by the object must be immutable as well, or it could be possible to change the state of the object.
For example, allowing an reference to an array or ArrayList to be obtained through an gette...
Difference between session affinity and sticky session?
...ation fails -- maybe you need to login again. Maybe you have lost data. Usually, the load-balancer picks another server and you keep going, but some state is lost. If this is unacceptable, then you need to get the state to the DB or other servers as quick as possible or have a stateless strategy.
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How to view or edit localStorage
...n tab. In the Storage section expand Local Storage. After that, you'll see all your browser's local storage there.
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