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How to check if all elements of a list matches a condition?
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The best answer here is to use all(), which is the builtin for this situation. We combine this with a generator expression to produce the result you want cleanly and efficiently. For example:
>>> items = [[1, 2, 0], [1, 2, 0], [1, 2, 0]]
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Representing graphs (data structure) in Python
...f._graph[node2].add(node1)
def remove(self, node):
""" Remove all references to node """
for n, cxns in self._graph.items(): # python3: items(); python2: iteritems()
try:
cxns.remove(node)
except KeyError:
pass
tr...
Stripping everything but alphanumeric chars from a string in Python
What is the best way to strip all non alphanumeric characters from a string, using Python?
11 Answers
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Creating a blocking Queue in .NET?
...threads reading from the same queue. If the queue reaches a specific size all threads that are filling the queue will be blocked on add until an item is removed from the queue.
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Installing Google Protocol Buffers on mac
I would like to install the older version of Google Protocol Buffers (protobuf-2.4.1) on mac using Terminal command line. I tried with brew install protobuf , but the latest version 2.5.0 has been installed. Is it possible to install the older version from terminal.
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Can modules have properties the same way that objects can?
...s? When I put this code in one file x.py and import it from another, then calling x.y results in AttributeError: 'NoneType' object has no attribute 'c', since _M somehow has value None...
– Stephan202
May 19 '09 at 1:35
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What is the best method to merge two PHP objects?
...bj_merged = (object) array_merge((array) $obj1, (array) $obj2);
This actually also works when objects have methods. (tested with PHP 5.3 and 5.6)
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Should all Python classes extend object?
...inheritance are different in ways that I won't even try to summarize here. All good documentation that I've seen about MI describes new-style classes.
Finally, old-style classes have disappeared in Python 3, and inheritance from object has become implicit. So, always prefer new style classes unless...
Why is it slower to iterate over a small string than a small list?
...nd with timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time.
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How do you query for “is not null” in Mongo?
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This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
d...