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How can I quantify difference between two images?
...s on the first image to edges on the second.
Is there noise in the image?
All sensors pollute the image with some amount of noise. Low-cost sensors have more noise. You may wish to apply some noise reduction before you compare images. Blur is the most simple (but not the best) approach here.
What k...
Best explanation for languages without null
... that every reference type gets this extra state in its space that is typically undesired. A string variable could be any sequence of characters, or it could be this crazy extra null value that doesn't map into my problem domain. A Triangle object has three Points, which themselves have X and Y va...
Efficiently updating database using SQLAlchemy ORM
...ngs in mind when using the ORM and plain SQL in the same transaction. Basically, from one side, ORM data modifications will only hit the database when you flush the changes from your session. From the other side, SQL data manipulation statements don't affect the objects that are in your session.
So...
What is the best way to implement nested dictionaries?
I have a data structure which essentially amounts to a nested dictionary. Let's say it looks like this:
21 Answers
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Is it intended by the C++ standards committee that in C++11 unordered_map destroys what it inserts?
... always move from its argument. It's supposed to move if the argument is really an rvalue, and copy if it's an lvalue.
The behaviour, you observe, which always moves, is a bug in libstdc++, which is now fixed according to a comment on the question. For those curious, I took a look at the g++-4.8 he...
Is module __file__ attribute absolute or relative?
...a file. The __file__ attribute is not present for C modules that are statically linked into the interpreter; for extension modules loaded dynamically from a shared library, it is the pathname of the shared library file.
From the mailing list thread linked by @kindall in a comment to the question:
...
ValidateAntiForgeryToken purpose, explanation and example
...icking the logged in user into submitting a form, or by simply programmatically triggering a form when the page loads.
The feature doesn't prevent any other type of data forgery or tampering based attacks.
To use it, decorate the action method or controller with the ValidateAntiForgeryToken attrib...
What is the instanceof operator in JavaScript?
...ce p inherits from Person.prototype.
Per the OP's request
I've added a small example with some sample code and an explanation.
When you declare a variable you give it a specific type.
For instance:
int i;
float f;
Customer c;
The above show you some variables, namely i, f, and c. The type...
Unit testing that events are raised in C# (in order)
...ited May 12 '11 at 15:38
David Hall
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answered Oct 30 '08 at 1:45
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rgdal package installation
...liam Kyngesburye at http://www.kyngchaos.com/ may be used for
source installs on OSX.
As you seem to be under Linux, you always build package from source, so you will have to install the corresponding libraries on your system. If you are under Mint, Ubuntu or another Debian derivative, you can d...