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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
...
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 ...
Are there legitimate uses for JavaScript's “with” statement?
...ous as to how I might make effective use of with , while avoiding its pitfalls.
31 Answers
...
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...
What is the difference between a field and a property?
...sed via get and set properties. Properties provide a level of abstraction allowing you to change the fields while not affecting the external way they are accessed by the things that use your class.
public class MyClass
{
// this is a field. It is private to your class and stores the actual da...
Pragma in define macro
...ay of doing that. Then again, there are no portable ways to use #pragma at all. Because of this, many C/C++ compilers define their own methods for doing pragma-like things, and they often can be embedded in macros, but you need a different macro definition on every compiler. If you are willing to go...
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...
What's the difference between __PRETTY_FUNCTION__, __FUNCTION__, __func__?
... = "function-name";
appeared, where function-name is the name of the lexically-enclosing function. This name is the unadorned name of the function.
Note that it is not a macro and it has no special meaning during preprocessing.
__func__ was added to C++ in C++11, where it is specified as containi...
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...
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(...