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Check if OneToOneField is None in Django
... Thank you for this solution. Unfortunately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasat...
Progress indicator during pandas operations
...se you're interested in how this works (and how to modify it for your own callbacks), see the examples on github, the full documentation on pypi, or import the module and run help(tqdm). Other supported functions include map, applymap, aggregate, and transform.
EDIT
To directly answer the original ...
How do I write a short literal in C++?
...rt enough to compile this as if it's a short literal (i.e. it wouldn't actually allocate an int and then cast it every time).
The following illustrates how much you should worry about this:
a = 2L;
b = 2.0;
c = (short)2;
d = '\2';
Compile -> disassemble ->
movl $2, _a
movl $2, _b
m...
Python: try statement in a single line
...ther dynamic languages. The safer way (and the prevailing style) is to set all variables to something. If they might not get set, set them to None first (or 0 or '' or something if it is more applicable.)
If you do assign all the names you are interested in first, you do have options.
The best...
Class method decorator with self arguments?
... @wraps(f)
def wrapped(self, *f_args, **f_kwargs):
if callable(_lambda) and search(pattern, (_lambda(self) or '')):
f(self, *f_args, **f_kwargs)
return wrapped
return wrapper
class MyTest(object):
def __init__(self):
self.name = 'foo'
...
Extract substring in Bash
...o-based) and "5" is the length. Also, +1 for @gontard 's link that lays it all out!
– Doktor J
Sep 12 '14 at 17:32
...
SQLAlchemy: cascade delete
...use that is where you defined your relationship (it doesn't care that you called it "Child" of course).
If you define the relationship on the Parent class instead, it will work:
children = relationship("Child", cascade="all,delete", backref="parent")
(note "Child" as a string: this is allowed wh...
Why / when would it be appropriate to override ToString?
...way? Yes.
But by using ToString you are using a method that is common to all objects and thus other classes know about this method. For instance, whenever the .NET framework wants to convert an object to a string representation, ToString is a prime candidate (there are others, if you want to provi...
Calling Objective-C method from C++ member function?
I have a class ( EAGLView ) which calls a member function of a C++ class without problems. Now, the problem is that I need to call in that C++ class a objective-C function [context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer*)self.layer]; which I cannot do in C++ syntax...
How to plot two columns of a pandas data frame using points?
...
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(...