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How do I find the length of an array?
...pression so it doesn't have any drawbacks over the macro (at least none I know of).
You can also consider using std::array from C++11 which exposes its length with no overhead over a native C array.
C++17 has std::size() in the <iterator> header which does the same and works for STL containe...
Notification click: activity already open
...es on top of it will be closed and
this Intent will be delivered to the (now on top) old activity as a
new Intent.
For example, consider a task consisting of the activities: A, B, C, D.
If D calls startActivity() with an Intent that resolves to the
component of activity B, then C and D...
Why aren't pointers initialized with NULL by default?
...ion point was he/she needed to perform some operation and then assign.
So now we have the situation that the compiler has added an extra instruction to the code that initializes the variable to NULL then later the developer code is added to do the correct initialization. Or under other conditions t...
android get real path by Uri.getPath()
...lver.openInputStream() allow you to access the contents of a file without knowing its real path.
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difference between variables inside and outside of __init__()
...e I could access both kind of variables through the self reference. It was now, when I ran into trouble, that I researched the topic and cleared it up.
The problem with accessing static class variables through the
self reference is that it only references the static class variable if there is no i...
Why does multiprocessing use only a single core after I import numpy?
....getpid())
With this line pasted in after the module imports, my example now runs on all cores:
My experience so far has been that this doesn't seem to have any negative effect on numpy's performance, although this is probably machine- and task-specific .
Update:
There are also two ways to di...
How to import and use different packages of the same name in Go language?
...
import (
"text/template"
htemplate "html/template" // this is now imported as htemplate
)
Read more about it in the spec.
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Get pandas.read_csv to read empty values as empty string instead of nan
...
Documentation for read_csv now offers both na_values (list or dict indexed by columns) and keep_default_na (bool). The keep_default_na value indicates whether pandas' default NA values should be replaced or appended to. The OP's code doesn't work curre...
Do declared properties require a corresponding instance variable?
...e Modern Objective-C Runtime (that's either iOS 3.x or greater, or 64-bit Snow Leopard or greater) then you do not need to define ivars for your properties in cases like this.
When you @synthesize the property, the ivar will in effect be synthesized also for you. This gets around the "fragile-ivar"...
Covariance and contravariance real world example
...e donkey gobbling code last week and i was so glad that we have covariance now. :-)
– Eric Lippert
Apr 18 '10 at 15:26
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