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Finding quaternion representing the rotation from one vector to another
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answered Jul 23 '09 at 14:04
Polaris878Polaris878
31.6k3535 gold badges105105 silver badges139139 bronze badges
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Checking images for similarity with OpenCV
...ue (maybe a percentage) that indicates how similar these images are? E.g. 100% would be returned if the same image was passed twice, 0% would be returned if the images were totally different.
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How to convert index of a pandas dataframe into a column?
...either:
df['index1'] = df.index
or, .reset_index:
df.reset_index(level=0, inplace=True)
so, if you have a multi-index frame with 3 levels of index, like:
>>> df
val
tick tag obs
2016-02-26 C 2 0.0139
2016-02-27 A 2 0.5577
2016-02-28 C ...
How to create GUID / UUID?
... be of the form "xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx", where x is one of [0-9, a-f] M is one of [1-5], and N is [8, 9, a, or b]
Use of a low-quality source of randomness (such as Math.random)
Thus, developers writing code for production environments are encouraged to use a rigorous, well-maintain...
Cron job every three days
Is it possible to run a cronjob every three days? Or maybe 10 times/month.
11 Answers
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How do I create a dictionary with keys from a list and values defaulting to (say) zero? [duplicate]
I have a = [1,2,3,4] and I want d = {1:0, 2:0, 3:0, 4:0}
5 Answers
5
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Return a value if no rows are found in Microsoft tSQL
...hat doesn't exist then I will get nothing returned. I'd prefer that false (0) is returned in that scenario. Looking for the simplest method to account for no records.
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How to print a percentage value in python?
...supports a percentage floating point precision type:
>>> print "{0:.0%}".format(1./3)
33%
If you don't want integer division, you can import Python3's division from __future__:
>>> from __future__ import division
>>> 1 / 3
0.3333333333333333
# The above 33% example wo...
How can I implode an array while skipping empty array items?
...ode('-', array_filter($array));
Obviously this will not work if you have 0 (or any other value that evaluates to false) in your array and you want to keep it. But then you can provide your own callback function.
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SQL statement to select all rows from previous day
...rom one table. The table holds one datetime column. I am using SQL Server 2005.
11 Answers
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