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How to draw a custom UIView that is just a circle - iPhone app
How would I go about drawing a custom UIView that is literally just a ball (a 2D circle)? Would I just override the drawRect method? And can someone show me the code for drawing a blue circle?
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What is the purpose of class methods?
...sson was that Python is not Java , and so I've just spent a while turning all my Class methods into functions.
17 Answers
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How do I clear only a few specific objects from the workspace?
I would like to remove some data from the workspace. I know the "Clear All" button will remove all data. However, I would like to remove just certain data.
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Explaining Python's '__enter__' and '__exit__'
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Using these magic methods (__enter__, __exit__) allows you to implement objects which can be used easily with the with statement.
The idea is that it makes it easy to build code which needs some 'cleandown' code executed (think of it as a try-finally block). Some more ex...
Flask-SQLAlchemy how to delete all rows in a single table
How do I delete all rows in a single table using Flask-SQLAlchemy?
3 Answers
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Wolfram's Rule 34 in XKCD [closed]
The hover "joke" in #505 xkcd touts "I call rule 34 on Wolfram's Rule 34".
12 Answers
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Managing constructors with many parameters in Java
...ing to keep track of any kind of argument order, since any order of those calls will work equally well.
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How to remove all whitespace from a string?
...\r\v\fy \t\n\r\v\f"
## [4] NA
The base R approach: gsub
gsub replaces all instances of a string (fixed = TRUE) or regular expression (fixed = FALSE, the default) with another string. To remove all spaces, use:
gsub(" ", "", x, fixed = TRUE)
## [1] "xy" "←→" ...
How do I build a numpy array from a generator?
... lists. This is necessary so that space for each item can be consecutively allocated in memory. Consecutive allocation is the key feature of numpy arrays: this combined with native code implementation let operations on them execute much quicker than regular lists.
Keeping this in mind, it is techni...
Which characters are valid in CSS class names/selectors?
What characters/symbols are allowed within the CSS class selectors?
I know that the following characters are invalid , but what characters are valid ?
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