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pandas GroupBy columns with NaN (missing) values
... from pandas 1.1 you have better control over this behavior, NA values are now allowed in the grouper using dropna=False
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How do I execute a string containing Python code in Python?
...pser you should be mych more concerned with using exec at all (unless you know the code string comes from a trusted source).
– bruno desthuilliers
Dec 2 '19 at 17:00
add a com...
What's the difference between dynamic (C# 4) and var?
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var is static typed - the compiler and runtime know the type - they just save you some typing... the following are 100% identical:
var s = "abc";
Console.WriteLine(s.Length);
and
string s = "abc";
Console.WriteLine(s.Length);
All that happened was that the compiler f...
Scala: write string to file in one statement
...if I look at /tmp/example.txt there is no.
– user unknown
Feb 9 '12 at 1:28
@user unknown, Sorry for missing out the '...
Is it alright to use target=“_blank” in HTML5?
... was no longer okay to use target="_blank" in HTML5, but I can't find it now.
9 Answers
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How to change a module variable from another module?
...till live in different namespaces: in __init__.py, they are bar.a and a).
Now, when you do
import bar
print bar.a
you are accessing variable bar/__init__.py:a (since import bar imports your bar/__init__.py). This is the variable you modify (to 1). You are not touching the contents of variable ...
What is the official “preferred” way to install pip and virtualenv systemwide?
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If you can install the latest Python (2.7.9 and up) Pip is now bundled with it.
See: https://docs.python.org/2.7//installing/index.html
If not :
Update (from the release notes):
Beginning with v1.5.1, pip does not require setuptools prior to running get-pip.py. Additionally, if ...
What is the use of “assert” in Python?
...ch evaluate to their contents. But with assert(False,) the parentheses are now a tuple, and a non-empty tuple evaluates to True in a boolean context.
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Is there a read-only generic dictionary available in .NET?
...d too, but at least with the interface it shouldn't be difficult to create now an implementation which exposes an official .NET generic interface :)
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When to use EntityManager.find() vs EntityManager.getReference() with JPA
...etter method). Just to change state (I mean setter method). As you should know, getReference returns a proxy object which uses a powerful feature called automatic dirty checking. Suppose the following
public class Person {
private String name;
private Integer age;
}
public class PersonS...