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List changes unexpectedly after assignment. How do I clone or copy it to prevent this?
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With new_list = my_list, you don't actually have two lists. The assignment just copies the reference to the list, not the actual list, so both new_list and my_list refer to the same list after the assignment.
To actually copy the list, you have various possibilit...
How do I get hour and minutes from NSDate?
...ateComponents:
Obj-C:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"<your date format goes here"];
NSDate *date = [dateFormatter dateFromString:string1];
NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calend...
Multiple constructors in python? [duplicate]
... Now you can do:
c = C(fd)
# or:
c = C.fromfilename('a filename')
Notice all those classmethods still go through the same __init__, but using classmethods can be much more convenient than having to remember what combinations of keyword arguments to __init__ work.
isinstance is best avoided becaus...
json_encode() escaping forward slashes
...zone.com/posts/show/7487 (archived copy).
Example Demo
<?php
/*
* Escaping the reverse-solidus character ("/", slash) is optional in JSON.
*
* This can be controlled with the JSON_UNESCAPED_SLASHES flag constant in PHP.
*
* @link http://stackoverflow.com/a/10210433/367456
*/
$url = '...
Pure JavaScript: a function like jQuery's isNumeric() [duplicate]
... way of doing this (then going ahead and using parseFloat, which doesn't really seem different). Interestingly isFinite will get you the result you're after in almost all cases on its own (apart from whitespace strings, which for some reason return true), so parseInt vs parseFloat seems irrelevant i...
C# Lambda expressions: Why should I use them?
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Expression trees are a very powerful new feature of C# 3.0 that allow an API to look at the structure of an expression instead of just getting a reference to a method that can be executed. An API just has to make a delegate parameter into an Expression<T> parameter and the compiler will gen...
ASP.NET: HTTP Error 500.19 – Internal Server Error 0x8007000d
... module (referenced in web.config) is missing or proper version is not installed.
Just install URL rewriting module via web platform installer.
I recommend to check all dependencies from web.config and install them.
share
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How to convert a String into an ArrayList?
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Hehe, yeah, +1 :-) It may actually even just be the split his after :P
– aioobe
Sep 8 '11 at 13:47
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Algorithm to detect overlapping periods [duplicate]
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I don't see how this covers all scenarios.
– doker
Sep 24 '14 at 10:55
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Numpy - add row to array
...2, 0]])
X = array([[0, 1, 2], [1, 2, 0], [2, 1, 2], [3, 2, 0]])
add to A all rows from X where the first element < 3:
import numpy as np
A = np.vstack((A, X[X[:,0] < 3]))
# returns:
array([[0, 1, 2],
[0, 2, 0],
[0, 1, 2],
[1, 2, 0],
[2, 1, 2]])
...