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Delete column from pandas DataFrame
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This answer isn't really correct - the pandas developers didn't, but that doesn't mean it is hard to do.
– wizzwizz4
Sep 30 '17 at 9:42
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PostgreSQL return result set as JSON array?
...up
The json_agg function produces this result out of the box. It automatically figures out how to convert its input into JSON and aggregates it into an array.
SELECT json_agg(t) FROM t
There is no jsonb (introduced in 9.4) version of json_agg. You can either aggregate the rows into an array and ...
Building a minimal plugin architecture in Python
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Mine is, basically, a directory called "plugins" which the main app can poll and then use imp.load_module to pick up files, look for a well-known entry point possibly with module-level config params, and go from there. I use file-monitorin...
Best practice: PHP Magic Methods __set and __get [duplicate]
...magic methods.
This was a mistake, the last part of your question says it all :
this is slower (than getters/setters)
there is no auto-completion (and this is a major problem actually), and type management by the IDE for refactoring and code-browsing (under Zend Studio/PhpStorm this can be handle...
General guidelines to avoid memory leaks in C++ [closed]
... programs? How do I figure out who should free memory that has been dynamically allocated?
29 Answers
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How to plot two columns of a pandas data frame using points?
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You can specify the style of the plotted line when calling df.plot:
df.plot(x='col_name_1', y='col_name_2', style='o')
The style argument can also be a dict or list, e.g.:
import numpy as np
import pandas as pd
d = {'one' : np.random.rand(10),
'two' : np.random.rand(...
How many and which are the uses of “const” in C++?
...structor of it doesn't need to be virtual - the right destructor is still called:
ScopeGuard const& guard = MakeGuard(&cleanUpFunction);
Explanation, using code:
struct ScopeGuard {
~ScopeGuard() { } // not virtual
};
template<typename T> struct Derived : ScopeGuard {
T ...
foldl versus foldr behavior with infinite lists
...ed. If f always uses its first argument, this means Haskell has to recurse all the way down to the innermost term, then work backwards computing each application of f.
This is obviously a far cry from the efficient tail-recursion most functional programmers know and love!
In fact, even though fold...
How to set custom header in Volley Request
...longwith. I don't see how JsonRequest class supports it. Is it possible at all?
13 Answers
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What is the boundary in multipart/form-data?
...ust the 'key' to separate the multiple "parts" of a multipart payload. Normally something like '&' is enough to separate the variables but you need something more unique to separate the payloads within the payload.
– user2483724
Mar 18 '14 at 18:30
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