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How is Math.Pow() implemented in .NET Framework?
...king for an efficient approach for calculating a b (say a = 2 and b = 50 ). To start things up, I decided to take a look at the implementation of Math.Pow() function. But in .NET Reflector , all I found was this:
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[] and {} vs list() and dict(), which is better?
...s/dicts:
>>> from timeit import timeit
>>> timeit("[]")
0.040084982867934334
>>> timeit("list()")
0.17704233359267718
>>> timeit("{}")
0.033620194745424214
>>> timeit("dict()")
0.1821558326547077
and for non-empty:
>>> timeit("[1,2,3]")
0.243...
How do I find the time difference between two datetime objects in python?
...; difference = later_time - first_time
>>> seconds_in_day = 24 * 60 * 60
datetime.timedelta(0, 8, 562000)
>>> divmod(difference.days * seconds_in_day + difference.seconds, 60)
(0, 8) # 0 minutes, 8 seconds
Subtracting the later time from the first time difference = later_tim...
Detect if value is number in MySQL
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answered Feb 21 '11 at 10:47
RichardTheKiwiRichardTheKiwi
96.3k2323 gold badges178178 silver badges250250 bronze badges
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How to create a density plot in matplotlib?
... [4.5]*3 + [5.5]*1 + [6.5]*8
density = gaussian_kde(data)
xs = np.linspace(0,8,200)
density.covariance_factor = lambda : .25
density._compute_covariance()
plt.plot(xs,density(xs))
plt.show()
I get
which is pretty close to what you are getting from R. What have I done? gaussian_kde uses a changa...
How to pass arguments and redirect stdin from a file to program run in gdb?
... |
edited Dec 23 '10 at 17:32
answered Dec 23 '10 at 17:21
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Getting the first character of a string with $str[0]
I want to get the first letter of a string and I've noticed that $str[0] works great. I am just not sure whether this is 'good practice', as that notation is generally used with arrays. This feature doesn't seem to be very well documented so I'm turning to you guys to tell me if it's all right –...
How to iterate a loop with index and element in Swift
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Yes. As of Swift 3.0, if you need the index for each element along with its value, you can use the enumerated() method to iterate over the array. It returns a sequence of pairs composed of the index and the value for each item in the array. For...
What does |= (ior) do in Python?
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Here we apply merge (|) and update (|=) to dicts:
>>> d1 = {"a": 0, "b": 1, "c": 2}
>>> d2 = {"c": 20, "d": 30}
>>> # Merge, |
>>> d1 | d2
{"a": 0, "b": 1, "c": 20, "d": 30}
>>> d1
{"a": 0, "b": 1, "c": 2}
>>> # Update, |=
>>> d1 |=...
Change Active Menu Item on Page Scroll?
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207
It's done by binding to the scroll event of the container (usually window).
Quick example:
//...