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List of zeros in python [duplicate]
... only zeros? I want to be able to create a zeros list for each int in range(10)
8 Answers
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What is the difference between atan and atan2 in C++?
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One small detail, the range -π/2 <= atan() <= π/2 actually includes one point (pi/2) from quadrant II.
– Z boson
Jul 2 '15 at 11:30
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Get type of all variables
...ly) #a function is function
class(charToRaw("hi")) #convert string to raw: raw
class(array("hi")) #array of items is: array
#So far so good, but those who wish to keep their sanity go no further
class(5 + 5L) #do...
What's the function like sum() but for multiplication? product()?
...iterable):
return reduce(operator.mul, iterable, 1)
>>> prod(range(1, 5))
24
Note, in Python 3, the reduce() function was moved to the functools module.
Specific case: Factorials
As a side note, the primary motivating use case for prod() is to compute factorials. We already have supp...
Python Process Pool non-daemonic?
...procs)
result = pool.map(sleepawhile,
[randint(1, 5) for x in range(num_procs)])
# The following is not really needed, since the (daemon) workers of the
# child's pool are killed when the child is terminated, but it's good
# practice to cleanup after ourselves anyway.
p...
Git diff between current branch and master but not including unmerged master commits
... in gitrevisions[7]. However, "diff" is about comparing two endpoints, not ranges, and the range notations ("<commit>..<commit>" and "<commit>...<commit>") do not mean a range as defined in the "SPECIFYING RANGES" section in gitrevisions[7].
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Shared-memory objects in multiprocessing
...e = t
a = SharedNumpyMemManager.getArray(shm_hdl)
for j in range(INNER_LOOP):
a[i] = i
class Parallel_Dummy_PF:
def __init__(self, N):
self.N = N
self.arrayHdl = SharedNumpyMemManager.createArray(self.N, ctype=ctypes.c_double) ...
Python: Why is functools.partial necessary?
... return partial(math.sin, x)
Iter = 10**7
start = time.clock()
for i in range(0, Iter):
l = make_lambda()
stop = time.clock()
print('lambda creation time {}'.format(stop - start))
start = time.clock()
for i in range(0, Iter):
l()
stop = time.clock()
print('lambda execution time {}'.forma...
How do I interpret precision and scale of a number in a database?
...gt; could be truncated into 123.46 (p=5,s=2)
123450 (p=6,s=0) => out of range
Note that the range is generally defined by the precision: |value| < 10^p ...
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SQL “between” not inclusive
...ETWEEN which does include BOTH the lower value and the upper values in the range, but does not magically make a date the "beginning of" or "the end of".
BETWEEN should be avoided when filtering by date ranges.
Always use the >= AND < instead
SELECT * FROM Cases
WHERE (created_at >= '2...