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How do you detect where two line segments intersect? [closed]

...f r × s = 0 and (q − p) × r ≠ 0, then the two lines are parallel and non-intersecting. If r × s ≠ 0 and 0 ≤ t ≤ 1 and 0 ≤ u ≤ 1, the two line segments meet at the point p + t r = q + u s. Otherwise, the two line segments are not parallel but do not intersect....
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Multiprocessing vs Threading Python [duplicate]

... There is actually a good deal of difference: eli.thegreenplace.net/2012/01/16/… – Andrew Sledge May 29 '13 at 11:36 ...
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In Django, how do I check if a user is in a certain group?

...add(group) # user is now in the "Editor" group then user.groups.all() returns [<Group: Editor>]. Alternatively, and more directly, you can check if a a user is in a group by: if django_user.groups.filter(name = groupname).exists(): ... Note that groupname can also be the ac...
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Clicking the text to select corresponding radio button

I'm creating a quiz web application using PHP. Each question is comprised of a separate <label> and has 4 possible choices, using radio buttons to allow the user to select his/her answer. The current HTML for a single question looks like: ...
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Objective-C and Swift URL encoding

...ww"; NSString *escapedString = [unescaped stringByAddingPercentEncodingWithAllowedCharacters:[NSCharacterSet URLHostAllowedCharacterSet]]; NSLog(@"escapedString: %@", escapedString); NSLog output: escapedString: http%3A%2F%2Fwww The following are useful URL encoding character sets: URLFragm...
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Calculate difference in keys contained in two Python dictionaries

...s: diff = set(dictb.keys()) - set(dicta.keys()) Here is a class to find all the possibilities: what was added, what was removed, which key-value pairs are the same, and which key-value pairs are changed. class DictDiffer(object): """ Calculate the difference between two dictionaries as: ...
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'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?

... and tests whether both expressions are logically True while & (when used with True/False values) tests if both are True. In Python, empty built-in objects are typically treated as logically False while non-empty built-ins are logically True. This facilitates the c...
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Python threading.timer - repeat function every 'n' seconds

... not self.stopped.wait(0.5): print("my thread") # call a function In the code that started the timer, you can then set the stopped event to stop the timer. stopFlag = Event() thread = MyThread(stopFlag) thread.start() # this will stop the timer stopFlag.set() ...
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Any way to make a WPF textblock selectable?

How to allow TextBlock 's text to be selectable? 15 Answers 15 ...
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How to get the return value from a thread in python?

...ram in param_list] The order will be maintained, and exiting the with will allow result collection. [f.result() for f in futures] – jayreed1 Jun 4 at 21:29 ...