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Why doesn't the example compile, aka how does (co-, contra-, and in-) variance work?
... meant "Object[] arr = new Integer[1];".
– Emre Sevinç
Jan 2 '13 at 13:46
2
...
Writing a list to a file with Python
...', 'w') as f:
for item in my_list:
f.write("%s\n" % item)
In Python 2, you can also use
with open('your_file.txt', 'w') as f:
for item in my_list:
print >> f, item
If you're keen on a single function call, at least remove the square brackets [], so that the strings...
Convert python datetime to epoch with strftime
...
If you want to convert a python datetime to seconds since epoch you could do it explicitly:
>>> (datetime.datetime(2012,04,01,0,0) - datetime.datetime(1970,1,1)).total_seconds()
1333238400.0
In Python 3.3+ you can use timestamp() instead:...
Get: TypeError: 'dict_values' object does not support indexing when using python 3.2.3 [duplicate]
...
In Python 3, dict.values() (along with dict.keys() and dict.items()) returns a view, rather than a list. See the documentation here. You therefore need to wrap your call to dict.values() in a call to list like so:
v = list(d.va...
How do I use method overloading in Python?
I am trying to implement method overloading in Python:
15 Answers
15
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Python `if x is not None` or `if not x is None`?
...
There's no performance difference, as they compile to the same bytecode:
Python 2.6.2 (r262:71600, Apr 15 2009, 07:20:39)
>>> import dis
>>> def f(x):
... return x is not None
...
>>> dis.dis(f)
2 0 LOAD_FAST 0 (x)
3 LOAD_CONST...
Python's time.clock() vs. time.time() accuracy?
Which is better to use for timing in Python? time.clock() or time.time()? Which one provides more accuracy?
16 Answers
...
Why is parenthesis in print voluntary in Python 2.7?
In Python 2.7 both the following will do the same
4 Answers
4
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How do you read a file into a list in Python? [duplicate]
...en find the mean, standard deviation, etc. without using the easy built-in Python tools.
8 Answers
...
Python Graph Library [closed]
I'm writing a python application that will make heavy use of a graph data structure. Nothing horribly complex, but I'm thinking some sort of graph/graph-algorithms library would help me out. I've googled around, but I don't find anything that particularly leaps out at me.
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