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M_PI works with math.h but not with cmath in Visual Studio
...) and suddenly it compile perfectly.
Try moving it higher up the page. Totally unsure as to why this would cause issues though.
Edit: Figured it out. The #include <math.h> occurs within cmath's header guards. This means that something higher up the list of #includes is including cmath with...
Super-simple example of C# observer/observable with delegates
...
The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empt...
Embed SVG in SVG?
...nteresting observation: the latest versions of Firefox, Chrome, and Safari all show only one level of recursion (two dots) using the above. However, if you save the above as "a.svg" and change the image to "b.svg", and then also save it as "b.svg" with the image referencing "a.svg", then Firefox wil...
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...
Convert nested Python dict to object?
...; s.a
1
>>> s.b
{'c': 2}
>>> s.c
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'MyStruct' object has no attribute 'c'
>>> s.d
['hi']
The alternative (original answer contents) is:
class Struct:
def __init__(self...
git command to move a folder inside another
...
Command:
$ git mv oldFolderName newFolderName
It usually works fine.
Error "bad source ..." typically indicates that after last commit there were some renames in the source directory and hence git mv cannot find the expected file.
The solution is simple - just commit before ...
How to make URL/Phone-clickable UILabel?
...TextView.editable = NO;
yourTextView.dataDetectorTypes = UIDataDetectorTypeAll;
Swift:
yourTextView.editable = false;
yourTextView.dataDetectorTypes = UIDataDetectorTypes.All;
This will detect links automatically.
See the documentation for details.
...
When to use enumerateObjectsUsingBlock vs. for
...
Ultimately, use whichever pattern you want to use and comes more naturally in the context.
While for(... in ...) is quite convenient and syntactically brief, enumerateObjectsUsingBlock: has a number of features that may or may not prove interesting:
enumerateObjectsUsingBlock: will be as fas...
What is an ORM, how does it work, and how should I use one? [closed]
... case with a pseudo language:
You have a book class, you want to retrieve all the books of which the author is "Linus". Manually, you would do something like that:
book_list = new List();
sql = "SELECT book FROM library WHERE author = 'Linus'";
data = query(sql); // I over simplify ...
while (row ...
How to correctly use “section” tag in HTML5?
...ion. A section, in this context, is a thematic grouping of
content, typically with a heading.
Examples of sections would be chapters, the various tabbed pages in a
tabbed dialog box, or the numbered sections of a thesis. A Web site's
home page could be split into sections for an introduct...