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What is getattr() exactly and how do I use it?
... understand about getattr() is that getattr(li, "pop") is the same as calling li.pop .
14 Answers
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How to execute a raw update sql with dynamic binding in rails
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It doesn't look like the Rails API exposes methods to do this generically. You could try accessing the underlying connection and using it's methods, e.g. for MySQL:
st = ActiveRecord::Base.connection.raw_connection.prepare("update table set f1=? where f2=? and f3=?")
st.execute(f1, f2, f3)
st...
Error when changing to master branch: my local changes would be overwritten by checkout
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Oops, mistyped add when it is actually save.. updated. You mean, for other files? git stash save without file name parameter will save all modified files, if you want to (and revert them to latest-commited state). And having extra copy of directory tree never...
Prepend a level to a pandas MultiIndex
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This is especially nice for adding a level to the columns by adding axis=1, since the df.columns doesn't have the "set_index" method like the index, which always bugs me.
– Rutger Kassies
Feb 10 '17 a...
MongoDB/NoSQL: Keeping Document Change History
... changes to one or more specific entities in a database. I've heard this called row versioning, a log table or a history table (I'm sure there are other names for it). There are a number of ways to approach it in an RDBMS--you can write all changes from all source tables to a single table (more of...
Git Push Error: insufficient permission for adding an object to repository database
...e).
The operating system doesn't interpret a setgid bit on directories as "all new files and subdirectories should inherit the group owner".
When core.sharedRepository is true or group, Git relies on a feature of GNU operating systems (e.g., every Linux distribution) to ensure that newly created su...
Python “raise from” usage
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@laike9m: you mean when you are handling exception foo, and want to raise a new exception bar? Then you can use raise bar from foo and have Python state that foo directly caused bar. If you don't use from foo, then Python will still print both, but state that during handling ...
How to compare two colors for similarity/difference
...d with what percentage. The thing is that I don't know how to do that manually step by step. So it is even more difficult to think of a program.
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How to sort with a lambda?
...lt;iterator>
#include <iostream>
#include <sstream>
struct Foo
{
Foo() : _i(0) {};
int _i;
friend std::ostream& operator<<(std::ostream& os, const Foo& f)
{
os << f._i;
return os;
};
};
typedef std::vector<Foo> Vect...
How can I split and parse a string in Python?
...t a string on space, get a list, show its type, print it out:
el@apollo:~/foo$ python
>>> mystring = "What does the fox say?"
>>> mylist = mystring.split(" ")
>>> print type(mylist)
<type 'list'>
>>> print mylist
['What', 'does', 'the', 'fox', 'say?']
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