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In-memory size of a Python structure
...g/measure-real-size-any-python-object/
The punchline:
import sys
def get_size(obj, seen=None):
"""Recursively finds size of objects"""
size = sys.getsizeof(obj)
if seen is None:
seen = set()
obj_id = id(obj)
if obj_id in seen:
return 0
# Important mark as s...
Avoid duplicates in INSERT INTO SELECT query in SQL Server
...
Using NOT EXISTS:
INSERT INTO TABLE_2
(id, name)
SELECT t1.id,
t1.name
FROM TABLE_1 t1
WHERE NOT EXISTS(SELECT id
FROM TABLE_2 t2
WHERE t2.id = t1.id)
Using NOT IN:
INSERT INTO TABLE_2
(id, name)
SELECT t...
Convert string to binary in python
...encoding.
In Python 3, then, you can do something like this:
a = "test"
a_bytes = bytes(a, "ascii")
print(' '.join(["{0:b}".format(x) for x in a_bytes]))
The differences between UTF-8 and ascii encoding won't be obvious for simple alphanumeric strings, but will become important if you're process...
UnicodeDecodeError: 'ascii' codec can't decode byte 0xef in position 1
...your terminal not being set to UTF-8. Here is my terminal
$ echo $LANG
en_GB.UTF-8
$ python
Python 2.7.3 (default, Apr 20 2012, 22:39:59)
[GCC 4.6.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> s = '(\xef\xbd\xa1\xef\xbd\xa5\xcf\x89\xef\xbd\xa5\xe...
Best way to strip punctuation from a string
..."","")
regex = re.compile('[%s]' % re.escape(string.punctuation))
def test_set(s):
return ''.join(ch for ch in s if ch not in exclude)
def test_re(s): # From Vinko's solution, with fix.
return regex.sub('', s)
def test_trans(s):
return s.translate(table, string.punctuation)
def test...
Is there a benefit to defining a class inside another class in Python?
... use a metaclass, it's sometimes handy to do
class Foo(object):
class __metaclass__(type):
....
instead of defining a metaclass separately, if you're only using it once.
The only other time I've used nested classes like that, I used the outer class only as a namespace to group a bun...
What is the purpose of class methods?
...alling class methods of an object is "better", or "more idiomatic": obj.cls_mthd(...) or type(obj).cls_mthd(...)?
– Alexey
Feb 27 '18 at 12:43
...
Creating an abstract class in Objective-C
... format:@"You must override %@ in a subclass", NSStringFromSelector(_cmd)];
If your method returns a value, it's a bit easier to use
@throw [NSException exceptionWithName:NSInternalInconsistencyException
reason:[NSString stringWithFormat:@"You must override %...
Replacing some characters in a string with another character
...zLMN and I want to replace all the occurrences of x , y , and z with _ .
5 Answers
...
Javascript regex returning true.. then false.. then true.. etc [duplicate]
...
/^[^-_]([a-z0-9-_]{4,20})[^-_]$/gi;
You're using a g (global) RegExp. In JavaScript, global regexen have state: you call them (with exec, test etc.) the first time, you get the first match in a given string. Call them again and ...