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Does Python have a string 'contains' substring method?
...methods to make in available to your custom type.
– BallpointBen
Aug 17 '18 at 7:02
31
Just make ...
Use cases for the 'setdefault' dict method
...e case: Grouping items (in unsorted data, else use itertools.groupby)
# really verbose
new = {}
for (key, value) in data:
if key in new:
new[key].append( value )
else:
new[key] = [value]
# easy with setdefault
new = {}
for (key, value) in data:
group = new.setdefault(k...
C Macro definition to determine big endian or little endian machine?
...
Code supporting arbitrary byte orders, ready to be put into a file called order32.h:
#ifndef ORDER32_H
#define ORDER32_H
#include <limits.h>
#include <stdint.h>
#if CHAR_BIT != 8
#error "unsupported char size"
#endif
enum
{
O32_LITTLE_ENDIAN = 0x03020100ul,
O32_BIG_END...
std::enable_if to conditionally compile a member function
... I want to use std::enable_if to choose between two member-functions and allow only one of them to be used.
7 Answers
...
How to find the installed pandas version
...trouble with some of pandas functionalities. How do I check what is my installation version?
6 Answers
...
How to track down a “double free or corruption” error
...
If you're using glibc, you can set the MALLOC_CHECK_ environment variable to 2, this will cause glibc to use an error tolerant version of malloc, which will cause your program to abort at the point where the double free is done.
You can set this from gdb by using ...
ASP.NET MVC - Set custom IIdentity or IPrincipal
...ver is easier / more suitable. I want to extend the default so that I can call something like User.Identity.Id and User.Identity.Role . Nothing fancy, just some extra properties.
...
django change default runserver port
...
You can't run the development server programmatically, so a custom command won't work unless it calls the shell using something like call. If this solution works for you please make sure to mark it as solved.
– Pablo Albornoz
May 13 '1...
Flask-SQLalchemy update a row's information
...e many objects to be updated.
If you want to give add_user permission to all the admins,
rows_changed = User.query.filter_by(role='admin').update(dict(permission='add_user'))
db.session.commit()
Notice that filter_by takes keyword arguments (use only one =) as opposed to filter which takes an e...
Length of generator output [duplicate]
... Fibonacci numbers. You can get as many Fibonacci numbers as you want by calling next().
If you really need to know the number of items there are, then you can't iterate through them linearly one time anyway, so just use a different data structure such as a regular list.
...