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How to serialize SqlAlchemy result to JSON?
... flat implementation
You could use something like this:
from sqlalchemy.em>x m>t.declarative import DeclarativeMeta
class AlchemyEncoder(json.JSONEncoder):
def default(self, obj):
if isinstance(obj.__class__, DeclarativeMeta):
# an SQLAlchemy class
fields = {}
...
Pandas groupby: How to get a union of strings
...
dtype: object
When you apply your own function, there is not automatic em>x m>clusions of non-numeric columns. This is slower, though, than the application of .sum() to the groupby
In [8]: df.groupby('A').apply(lambda m>x m>: m>x m>.sum())
Out[8]:
A B C
A
1 2 1....
Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...h greatly slows down the performance. (In contrast, Intel C++ Compiler , em>x m>ecutable icc , will eliminate the library call for pow(a,6) .)
...
How is null + true a string?
...om the C# language spec.
From section 7.3.4:
An operation of the form m>x m> op y, where op is an overloadable binary operator, m>x m> is an em>x m>pression of type m>X m>, and y is an em>x m>pression of type Y, is processed as follows:
The set of candidate user-defined operators provided by m>X m> and Y for the ope...
How does a ArrayList's contains() method evaluate objects?
...object and add it to my ArrayList . If I then create another object with em>x m>actly the same constructor input, will the contains() method evaluate the two objects to be the same? Assume the constructor doesn't do anything funny with the input, and the variables stored in both objects are identical....
Fastest way to check if a value em>x m>ists in a list
What is the fastest way to know if a value em>x m>ists in a list (a list with millions of values in it) and what its indem>x m> is?
1...
List OrderBy Alphabetical Order
... looking to quickly sort a Generic List<T> . For the sake of this em>x m>ample, let's say I have a List of a Person type with a property of lastname. How would I sort this List using a lambda em>x m>pression?
...
Iterating over a numpy array
...erate.
>>> a =numpy.array([[1,2],[3,4],[5,6]])
>>> for (m>x m>,y), value in numpy.ndenumerate(a):
... print m>x m>,y
...
0 0
0 1
1 0
1 1
2 0
2 1
Regarding the performance. It is a bit slower than a list comprehension.
m>X m> = np.zeros((100, 100, 100))
%timeit list([((i,j,k), m>X m>[i,j,k]) fo...
Calling filter returns [duplicate]
...
It looks like you're using python 3.m>x m>. In python3, filter, map, zip, etc return an object which is iterable, but not a list. In other words,
filter(func,data) #python 2.m>x m>
is equivalent to:
list(filter(func,data)) #python 3.m>x m>
I think it was changed becau...