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Can PostgreSQL index array columns?
...ices) instead of building a more expensive expression index for each array item. Storage of individual columns is much cheaper without array overhead, too.
– Erwin Brandstetter
Mar 25 '15 at 1:09
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What are “named tuples” in Python?
...lots__:
yield getattr(self, name)
# Sequence requires __getitem__ & __len__:
def __getitem__(self, index):
return getattr(self, self.__slots__[index])
def __len__(self):
return len(self.__slots__)
And to use, just subclass and define __slots__:
class St...
How do I check if a string is a number (float)?
What is the best possible way to check if a string can be represented as a number in Python?
33 Answers
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How to synchronize a static variable among threads running different instances of a class in Java?
...d (countLock) {
count++;
}
}
}
Method 3 is the best in many cases because the lock object is not exposed outside of your class.
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Evaluating a mathematical expression in a string
...st.
import ast, math
locals = {key: value for (key,value) in vars(math).items() if key[0] != '_'}
locals.update({"abs": abs, "complex": complex, "min": min, "max": max, "pow": pow, "round": round})
class Visitor(ast.NodeVisitor):
def visit(self, node):
if not isinstance(node, self.whi...
Test if something is not undefined in JavaScript
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this is the best way if you are testing if a function is undefined
– edepperson
Mar 12 '14 at 1:28
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How is attr_accessible used in Rails 4?
...tr_accessible in you models like in Rails 3
Also, and i think that is the best way- using form objects for dealing with mass assignment, and saving nested objects, and you can also use protected_attributes gem that way
class NestedForm
include ActiveModel::MassAssignmentSecurity
attr_access...
UIlabel layer.cornerRadius not working in iOS 7.1
...
I think the best way to set corner radius is:
and be sure the "Clip Subviews" is checked:
Checking "Clip Subviews" is equal to the code addMessageLabel.clipsToBounds = YES;.
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Truncating floats in Python
...ion (it produces 0.0000000002999999999999999980), and I'm not yet sure how best to handle those.
If you actually are working with floats that are very close to round numbers but intentionally not equal to them (like 0.29999999999999998 or 99.959999999999994), this will produce some false positives,...
Share data between AngularJS controllers
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First solution worked best for me -- had the service maintain the object and the controllers just handle with the reference. Mucho thanks.
– johnkeese
Feb 21 '14 at 16:29
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