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Add column with constant value to pandas dataframe [duplicate]
...ods to gain some intuition for alignment works with objects that have partially, totally, and not-aligned-all aligned indices. For example here's how DataFrame.align() works with partially aligned indices:
In [7]: from pandas import DataFrame
In [8]: from numpy.random import randint
In [9]: df = ...
ASP.NET MVC JsonResult Date Format
...answer.
The JSON spec does not account for Date values. MS had to make a call, and the path they chose was to exploit a little trick in the javascript representation of strings: the string literal "/" is the same as "\/", and a string literal will never get serialized to "\/" (even "\/" must be map...
Correct way to use _viewstart.cshtml and partial Razor views?
I'm using _viewstart.cshtml to automagically assign the same Razor Layout to my views.
1 Answer
...
String formatting in Python 3
...format(goals=2, penalties=4)
"({goals} goals, ${penalties})".format(**self.__dict__)
"first goal: {0.goal_list[0]}".format(self)
"second goal: {.goal_list[1]}".format(self)
"conversion rate: {:.2f}".format(self.goals / self.shots) # '0.20'
"conversion rate: {:.2%}".format(self.goals / self.shots) ...
Most efficient way to create a zero filled JavaScript array?
... @PimpTrizkit arr = Array(n) and (arr = []).length = n behave identically according to the spec. In some implementations one could be faster, but I don't think there is a big difference.
– Oriol
Sep 22 '15 at 16:39
...
How do you test running time of VBA code?
...Counter. Google it for more info. Try pushing the following into a class, call it CTimer say, then you can make an instance somewhere global and just call .StartCounter and .TimeElapsed
Option Explicit
Private Type LARGE_INTEGER
lowpart As Long
highpart As Long
End Type
Private Declare Fu...
std::unique_ptr with an incomplete type won't compile
...
I find your first solution (adding the foo destructor) allows the class declaration itself to compile, but declaring an object of that type anywhere results in the original error ("invalid application of 'sizeof'...").
– Jeff Trull
Sep 30 '1...
Given a view, how do I get its viewController?
...nd
This macro avoids category pollution:
#define UIViewParentController(__view) ({ \
UIResponder *__responder = __view; \
while ([__responder isKindOfClass:[UIView class]]) \
__responder = [__responder nextResponder]; \
(UIViewController *)__responder; \
})
...
map vs. hash_map in C++
...tied to that key.
map is implemented as a balanced binary search tree (usually a red/black tree).
An unordered_map should give slightly better performance for accessing known elements of the collection, but a map will have additional useful characteristics (e.g. it is stored in sorted order, which...
How to read json file into java with simple JSON library
...
Well, you want to process all of the items in the array in a loop. My code just gets you the first item (a.get(0)) because that was the closest match to your original code. The json-simple documentation says a JSONArray is java.util.List, so you can...