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Selecting with complex criteria from pandas.DataFrame
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406
Sure! Setup:
>>> import pandas as pd
>>> from random import randint
>&gt...
How does RegexOptions.Compiled work?
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304
RegexOptions.Compiled instructs the regular expression engine to compile the regular expression...
Better way to check variable for null or empty string?
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10 Answers
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Active
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Difference in System. exit(0) , System.exit(-1), System.exit(1 ) in Java
...seful to know if something went wrong and what went wrong.
Exit code is
0 when execution went fine;
1, -1, whatever != 0 when some error occurred, you can use different values for different kind of errors.
If I'm correct exit codes used to be just positive numbers (I mean in UNIX) and according...
Can I change the checkbox size using CSS?
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440
It's a little ugly (due to the scaling up), but it works on most newer browsers:
input[type...
JavaScript get element by name
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250
The reason you're seeing that error is because document.getElementsByName returns a NodeList of ...
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...
Why is AJAX returning HTTP status code 0?
...application) the browser just stops uploading and returns status codes of 0 . Why does this happen?
20 Answers
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COUNT DISTINCT with CONDITIONS
...count(distinct tag) as tag_count,
count(distinct (case when entryId > 0 then tag end)) as positive_tag_count
from
your_table_name;
The first count(distinct...) is easy.
The second one, looks somewhat complex, is actually the same as the first one, except that you use case...when clause. In ...
How to find out the number of CPUs using python
...thony Sottile
33.3k99 gold badges6666 silver badges100100 bronze badges
answered Jun 17 '09 at 10:53
Nadia AlramliNadia Alramli
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