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How do you write multiline strings in Go?
... choice to write regular expression patterns as they usually contain non-standard escape sequences that would make the Go compiler complain of not double-escaped. It keeps the patterns clean and relatively readable.
– jimt
Oct 29 '11 at 1:35
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iPhone app signing: A valid signing identity matching this profile could not be found in your keycha
...r every invalid provisioning profile have a button "Renew". After renewing and downloading updated provisioning profile all seems to work as expected, so problem is definitely solved :)
Update: you may have to contact Apple to get a "Renew"-button, or they removed it -- and the solution is to just ...
How do I convert a pandas Series or index to a Numpy array? [duplicate]
...d for a conversion.
Note: This attribute is also available for many other pandas' objects.
In [3]: df['A'].values
Out[3]: Out[16]: array([1, 2, 3])
To get the index as a list, call tolist:
In [4]: df.index.tolist()
Out[4]: ['a', 'b', 'c']
And similarly, for columns.
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Converting bytes to megabytes
... it is not correct actually because mega means 1 000 000. There is a new standard name for 220 bytes, it is mebibyte (http://en.wikipedia.org/wiki/Mebibyte) and it gathers popularity.
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improv...
Printing Lists as Tabular Data
I am quite new to Python and I am now struggling with formatting my data nicely for printed output.
13 Answers
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How to access the ith column of a NumPy multidimensional array?
... reference is reflected in the original array.
– harmands
Oct 18 '16 at 14:21
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When to use Common Table Expression (CTE)
I have begun reading about Common Table Expression and cannot think of a use case where I would need to use them. They would seem to be redundant as the same can be done with derived tables. Is there something I am missing or not understanding well? Can someone give me a simple example of limitati...
Difference between HashSet and HashMap?
... does not allow duplicate values, what is the difference between HashMap and HashSet ?
19 Answers
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Is there a NumPy function to return the first index of something in an array?
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Yes, here is the answer given a NumPy array, array, and a value, item, to search for:
itemindex = numpy.where(array==item)
The result is a tuple with first all the row indices, then all the column indices.
For example, if an array is two dimensions and it contained your it...
Counting null and non-null values in a single query
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This works for Oracle and SQL Server (you might be able to get it to work on another RDBMS):
select sum(case when a is null then 1 else 0 end) count_nulls
, count(a) count_not_nulls
from us;
Or:
select count(*) - count(a), count(a) fro...