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Example for boost shared_mutex (multiple reads/one write)?
I have a multithreaded app that has to read some data often, and occasionally that data is updated. Right now a mutex keeps access to that data safe, but it's expensive because I would like multiple threads to be able to read simultaneously, and only lock them out when an update is needed (the updat...
How to assert two list contain the same elements in Python? [duplicate]
...h does exactly what you are looking for, as you can read from the python standard library documentation. The method is somewhat misleadingly named but it does exactly what you are looking for.
a and b have the same elements in the same number, regardless of their order
Here a simple example wh...
Django database query: How to get object by id?
...ror exception. What was confusing me was that the code below executed fine and returned a result set as expected:
Class.objects.all()
Tail of the traceback for the get() method:
File "django/db/models/loading.py", line 197, in get_models
self._populate()
File "django/db/models/loading.py", l...
How can I have linebreaks in my long LaTeX equations?
...swered May 18 '10 at 21:42
Alessandro CuttinAlessandro Cuttin
3,18211 gold badge2424 silver badges3434 bronze badges
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Missing include “bits/c++config.h” when cross compiling 64 bit program on 32 bit in Ubuntu
I am running the 32bit version of Ubuntu 10.10 and trying to cross compile to a 64 bit target. Based on my research, I have installed the g++-multilib package.
...
How to crop an image in OpenCV using Python
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remember that x and y are flipped. I missed this.
– markroxor
Aug 26 '18 at 9:31
15
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Chained method calls indentation style in Python [duplicate]
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The need for this style becomes more obvious as method names get longer and as methods start taking arguments:
return some_collection.get_objects(locator=l5) \
.get_distinct(case_insensitive=True) \
.filter(predicate=query(q5)) \
...
Android Studio needs JDK 7 for Android-L mac
I was trying to look how my app looks in material design and I would like to use the new cards lib.
My Problem is, that it's giving me this error within my gradle file and I need to fix that.
...
#1071 - Specified key was too long; max key length is 1000 bytes
...ing such long VARCHAR columns anyway, because the index will be very bulky and inefficient.
The best practice is to use prefix indexes so you're only indexing a left substring of the data. Most of your data will be a lot shorter than 255 characters anyway.
You can declare a prefix length per colu...
How to know if an object has an attribute in Python
...at, if the property is likely to be there most of the time, simply call it and either let the exception propagate, or trap it with a try/except block. This will likely be faster than hasattr. If the property is likely to not be there most of the time, or you're not sure, using hasattr will probably ...