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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...
How to create a custom string representation for a class object?
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@RobertSiemer Why? While his answer is not specifically targeting the OP's question, it's still helpful. It helped me. And at a glance, I don't see any question asking for instance implementation. So probably people land on this page first.
– akinuri
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What's the difference between lists and tuples?
.... A list on the other hand could be used to store multiple locations. Naturally one might want to add or remove locations from the list, so it makes sense that lists are mutable. On the other hand it doesn't make sense to add or remove items from an existing location - hence tuples are immutable.
T...
How do I diff the same file between two different commits on the same branch?
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The .. isn't really necessary, though it'll work with it (except in fairly old versions, maybe). You can also use git log or gitk to find SHA1s to use, should the two commits be very far apart. gitk also has a "diff selected -> this" and...
Super-simple example of C# observer/observable with delegates
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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...
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...
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...
Devise - How do I forbid certain users from signing in?
...is who he says he is.
You need something else to forbid him from using the site.
Authorization is a popular topic and there's a whole list of gems that can help you with it:
http://ruby-toolbox.com/categories/rails_authorization.html
Take your pick.
...
How to detect iPhone 5 (widescreen devices)?
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First of all, you shouldn't rebuild all your views to fit a new screen, nor use different views for different screen sizes.
Use the auto-resizing capabilities of iOS, so your views can adjust, and adapt any screen size.
That's not v...
git command to move a folder inside another
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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 ...