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Find the nth occurrence of substring in a string
... more Pythonic version of the straightforward iterative solution:
def find_nth(haystack, needle, n):
start = haystack.find(needle)
while start >= 0 and n > 1:
start = haystack.find(needle, start+len(needle))
n -= 1
return start
Example:
>>> find_nth("fo...
Aren't Python strings immutable? Then why does a + “ ” + b work?
...
Consider:
>>> a='asdf'
>>> a.__repr__
<method-wrapper '__repr__' of str object at 0x1091aab90>
>>> a='asdf'
>>> a.__repr__
<method-wrapper '__repr__' of str object at 0x1091aab90>
>>> a='qwer'
>>> a.__repr_...
逆向工程——二进制炸弹(CSAPP Project) - 操作系统(内核) - 清泛网 - 专注...
...了一下，差不多几十页的样子，发现其中有六个函数phase_1……phase_6，基本上也就可以确定就是这六个关卡了。
===============phase_1===============
知识点：string，函数调用，栈
用了差不多一个星期断断续续地寻找感觉的phase_1，最...
How can I create a unique constraint on my column (SQL Server 2008 R2)?
...
Or set column as unique from the SQL Query window:
alter table location_key drop constraint pinky;
alter table your_table add constraint pinky unique(yourcolumn);
Changes take effect immediately:
Command(s) completed successfully.
...
hasNext in Python iterators?
...icult to write an adaptor that stores the result of next() and provides has_next() and move_next().
– avakar
Dec 24 '12 at 21:10
6
...
How to plot two columns of a pandas data frame using points?
...specify the style of the plotted line when calling df.plot:
df.plot(x='col_name_1', y='col_name_2', style='o')
The style argument can also be a dict or list, e.g.:
import numpy as np
import pandas as pd
d = {'one' : np.random.rand(10),
'two' : np.random.rand(10)}
df = pd.DataFrame(d)
df....
Tracking the script execution time in PHP
...amount of CPU time a particular script has used in order to enforce the max_execution_time limit.
18 Answers
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What is the best method to merge two PHP objects?
...
If your objects only contain fields (no methods), this works:
$obj_merged = (object) array_merge((array) $obj1, (array) $obj2);
This actually also works when objects have methods. (tested with PHP 5.3 and 5.6)
sha...
Why does sys.exit() not exit when called inside a thread in Python?
...from the thread?
Apart from the method Deestan described you can call os._exit (notice the underscore). Before using it make sure that you understand that it does no cleanups (like calling __del__ or similar).
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...
Wolfram's Rule 34 in XKCD [closed]
... There was also the XKCD strip that listed number of hits for "killed in a __________ accident" (for various activities), and noted something like two hits for "blogging". That number went up very fast after the strip came out.
– David Thornley
Dec 18 '09 at 2...