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Find row where values for column is maximal in a pandas DataFrame
... It's straightforward:
>>> import pandas
>>> import numpy as np
>>> df = pandas.DataFrame(np.random.randn(5,3),columns=['A','B','C'])
>>> df
A B C
0 1.232853 -1.979459 -0.573626
1 0.140767 0.394940 1.068890
2 0.742023 1.343977 -0.5...
Combining INSERT INTO and WITH/CTE
I have a very complex CTE and I would like to insert the result into a physical table.
3 Answers
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Split a collection into `n` parts with LINQ?
Is there a nice way to split a collection into n parts with LINQ?
Not necessarily evenly of course.
19 Answers
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Does Python's time.time() return the local or UTC timestamp?
Does time.time() in the Python time module return the system's time or the time in UTC?
8 Answers
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Entity Framework - Invalid Column Name '*_ID"
...n Code First and Database first EF, but I'm not sure how to fix it. I'll try to be as clear as I can, but I honestly am missing some of the understanding here myself. This is Entity Framework 4.4
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Why can a class not be defined as protected?
Why can we not define a class as protected ?
12 Answers
12
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In Postgresql, force unique on combination of two columns
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CREATE TABLE someTable (
id serial primary key,
col1 int NOT NULL,
col2 int NOT NULL,
unique (col1, col2)
)
autoincrement is not postgresql. You want a serial.
If col1 and col2 make a unique and can't be null then they make a good primary key:
CREATE...
C# difference between == and Equals()
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When == is used on an expression of type object, it'll resolve to System.Object.ReferenceEquals.
Equals is just a virtual method and behaves as such, so the overridden version will be used (which, for string type compares the contents).
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What is the benefit of using $() instead of backticks in shell scripts?
There are two ways to capture the output of command line in bash :
8 Answers
8
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What's the difference between lists and tuples?
...be pairs of page and line number to reference locations in a book, e.g.:
my_location = (42, 11) # page number, line number
You can then use this as a key in a dictionary to store notes on locations. A list on the other hand could be used to store multiple locations. Naturally one might want to a...