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Multiple aggregations of the same column using pandas GroupBy.agg()
... functions f1, f2 to the same column df["returns"] , without having to call agg() multiple times?
3 Answers
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How to check if all of the following items are in a list?
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Operators like <= in Python are generally not overriden to mean something significantly different than "less than or equal to". It's unusual for the standard library does this--it smells like legacy API to me.
Use the equivalent and more clearly-named method, ...
how do I make a single legend for many subplots with matplotlib?
... multiple subplots with matplotlib. That is, I have 9 plots on a 3x3 grid, all with the same for lines (of course, different values per line).
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How to join two sets in one line without using “|”
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You can use union method for sets: set.union(other_set)
Note that it returns a new set i.e it doesn't modify itself.
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Define variable to use with IN operator (T-SQL)
... myColumn in (SELECT id FROM myIdTable WHERE id > 10)
2) Using dynamically concatenated TSQL
DECLARE @sql varchar(max)
declare @list varchar(256)
select @list = '1,2,3'
SELECT @sql = 'SELECT * FROM myTable WHERE myColumn in (' + @list + ')'
exec sp_executeSQL @sql
3) A possible third ...
Why use Ruby's attr_accessor, attr_reader and attr_writer?
...write classes which will work correctly no matter how their public API is called.
class Person
attr_accessor :age
...
end
Here, I can see that I may both read and write the age.
class Person
attr_reader :age
...
end
Here, I can see that I may only read the age. Imagine that it is set ...
Subprocess changing directory
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@The_Diver That's why cd must be implemented as internal shell command. There's no other way to do it. Internal shell commands are executed within the same process as the shell. What I meant by subshell is the shell executed for ...
Creating instance of type without default constructor in C# using reflection
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I originally posted this answer here, but here is a reprint since this isn't the exact same question but has the same answer:
FormatterServices.GetUninitializedObject() will create an instance without calling a constructor. I found...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...the pointer to void * as in printf("%p", (void *)str); When printing a size_t with printf, you should use "%zu" if using the latest C standard (C99).
– Chris Young
Oct 3 '08 at 7:44
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Is nested function a good approach when required by only one function? [closed]
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>>> def sum(x, y):
... def do_it():
... return x + y
... return do_it
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>>> a = sum(1, 3)
>>> a
<function do_it at 0xb772b304>
>>> a()
4
Is this what you were looking for? It's called a closure.
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