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How can I quantify difference between two images?
...if they are color (RGB) images.
You will need these imports:
import sys
from scipy.misc import imread
from scipy.linalg import norm
from scipy import sum, average
Main function, read two images, convert to grayscale, compare and print results:
def main():
file1, file2 = sys.argv[1:1+2]
...
What is an “unwrapped value” in Swift?
...ar cantBeNil : Int = 4
cantBeNil = nil // can't do this
To get the value from your variable if it is optional, you have to unwrap it. This just means putting an exclamation point at the end.
var canBeNil : Int? = 4
println(canBeNil!)
Your code should look like this:
let optionalSquare: Square?...
What's the most efficient test of whether a PHP string ends with another string?
... I ran into a bug today which will break the solution that you have given from PHP 5.5.11 and onwards. bugs.php.net/bug.php?id=67043
– user2180613
Jul 29 '14 at 21:18
...
How do I enter a multi-line comment in Perl? [duplicate]
...ode and
Better ways to make multi-line comments in Perl for more
detail.
From faq.perl.org[perlfaq7]
How can I comment out a large block
of Perl code?
The quick-and-dirty way to comment out more than one line of Perl is
to surround those lines with Pod directives. You have to put these
...
How to upgrade R in ubuntu? [closed]
... one,so it is convenient to check this post. Then, follow the instructions from here
Open the sources.list file:
sudo nano /etc/apt/sources.list
Add a line with the source from where the packages will be retrieved. For example:
deb https://cloud.r-project.org/bin/linux/ubuntu/ version/
R...
C pointer to array/array of pointers disambiguation
...
@ankii You can install from Homebrew (and maybe MacPorts?). If those are not to your taste, it is trivial to build your own from the Github link on the top right of cdecl.org (I just built it on macOS Mojave). Then just copy the cdecl binary to yo...
WPF vs Silverlight [duplicate]
...rences like this a lot.
Within WPF, all visually rendering elements derive from the Visual base class. Within Silverlight, they do not; instead, they derive from Control. Both technologies, however, eventual derive from the DependencyObject class up the hierarchy.
WPF, currently, ships or has avai...
When to delete branches in Git?
...oping.
Delete old branches with
git branch -d branch_name
Delete them from the server with
git push origin --delete branch_name
or the old syntax
git push origin :branch_name
which reads as "push nothing into branch_name at origin".
That said, as long as the DAG (directed acyclic graph) ...
How do I implement __getattribute__ without an infinite recursion error?
...ive hell you were in before.
Ipython output with code in foo.py:
In [1]: from foo import *
In [2]: d = D()
In [3]: d.test
Out[3]: 0.0
In [4]: d.test2
Out[4]: 21
Update:
There's something in the section titled More attribute access for new-style classes in the current documentation, where the...
Asynchronous vs Multithreading - Is there a difference?
...g benefits on processor intensive tasks that are [ideally] able to benefit from the multiple processors, as well as benefits in asynchronous situations. Asynchrony == a process that does it's thing, while the state that called the process does not have to wait for it to complete. (Might not necessa...