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Circle line-segment collision detection algorithm?
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(x - h)2 + (y - k)2 = r2
(h,k) = center of circle.
Note: We've simplified the problem to 2D here, the solution we get applies also in 3D
to get:
Expand
x2 - 2xh + h2 + y2 - 2yk + k2 - r2 = 0
Plug
x = ex + tdx
y = ey + tdy
( ex + tdx )2 - 2( ex + tdx )h + h2 +
( ey + tdy )2 - 2( ey + tdy ...
What is the difference between 'my' and 'our' in Perl?
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Great question: How does our differ from my and what does our do?
In Summary:
Available since Perl 5, my is a way to declare non-package variables, that are:
private
new
non-global
separate from any package, so that the variable cannot be accessed i...
Nested attributes unpermitted parameters
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Seems there is a change in handling of attribute protection and now you must whitelist params in the controller (instead of attr_accessible in the model) because the former optional gem strong_parameters became part of the Rails Core.
This should look something like this:
class PeopleCo...
Draw in Canvas by finger, Android
...ngth - 1);
int i = (int)p;
p -= i;
// now p is just the fractional part [0...1) and i is the index
int c0 = colors[i];
int c1 = colors[i+1];
int a = ave(Color.alpha(c0), Color.alpha(c1), p);
int r = ave(Color.red(c0...
Vibrate and Sound defaults on notification
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The vibration now has a delay of 1000 ms. If you set the first one to 0, it will go off instantly. It's a { delay, vibrate, sleep, vibrate, sleep } pattern.
– Tom
Apr 30 '15 at 11:22
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Split Python Flask app into multiple files
...rint(account_api)
@app.route("/")
def hello():
return "Hello World!"
if __name__ == "__main__":
app.run()
AccountAPI.py
from flask import Blueprint
account_api = Blueprint('account_api', __name__)
@account_api.route("/account")
def accountList():
return "list of accounts"
If thi...
Real world example about how to use property feature in python?
...gth
@stride_length.setter
def stride_length(self, value):
if value > 10:
raise ValueError("This pedometer is based on the human stride - a stride length above 10m is not supported")
else:
self._stride_length = value
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In Python, if I return inside a “with” block, will the file still close?
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It is also mentioned in one of the examples of PEP-343 which is the specification for the with statement:
with locked(myLock):
# Code here executes with myLock held. The lock is
# guaranteed to be released when the block is left (even
# if via return or by an uncaught exception).
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fs: how do I locate a parent folder?
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@eyurdakul If I understand it corrently: __dirname may look like /path/to/your/dir, if you say __dirname + ".." it is /path/to/your/dir.., which is a nonexistent directory, rather than /path/to/your. The slash is important.
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Code equivalent to the 'let' keyword in chained LINQ extension method calls
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Woah, I didn't know you could autoencapsulate using the new operator like that.
– David Pfeffer
Sep 22 '10 at 15:31
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