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How to get first element in a list of tuples?
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do you mean something like this?
new_list = [ seq[0] for seq in yourlist ]
What you actually have is a list of tuple objects, not a list of sets (as your original question implied). If it is actually a list of sets, then there is no first element because set...
How can I have linebreaks in my long LaTeX equations?
...can be precisely controlled. e.g.
\begin{align*}
x&+y+\dots+\dots+x_100000000\\
&+x_100000001+\dots+\dots
\end{align*}
which would line up the first plus signs of each line... but obviously, you can set the alignments wherever you like.
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How to get the concrete class name as a string? [duplicate]
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instance.__class__.__name__
example:
>>> class A():
pass
>>> a = A()
>>> a.__class__.__name__
'A'
share
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Real life example, when to use OUTER / CROSS APPLY in SQL
... ORDER BY pr.name) pa
ORDER BY pr.name,
pa.name
2) Calling a Table Valued Function for each row in the outer query
SELECT *
FROM sys.dm_exec_query_stats AS qs
CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle)
3) Reusing a column alias
SELECT number,
doubled_number...
Programmatically get the cache line size?
All platforms welcome, please specify the platform for your answer.
8 Answers
8
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PHP: How to generate a random, unique, alphanumeric string for use in a secret link?
...of an application. In particular, rand() and uniqid() are not cryptographically secure random number generators. See Scott's answer for a secure alternative.
If you do not need it to be absolutely unique over time:
md5(uniqid(rand(), true))
Otherwise (given you have already determined a unique l...
How do I add the contents of an iterable to a set?
What is the "one [...] obvious way" to add all items of an iterable to an existing set ?
6 Answers
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Generating random whole numbers in JavaScript in a specific range?
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It's only doing that because it's calling floor, which rounds down.
– Josh Stodola
Oct 6 '09 at 20:17
6
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str performance in python
...; import dis
>>> dis.dis(lambda: str(100000))
8 0 LOAD_GLOBAL 0 (str)
3 LOAD_CONST 1 (100000)
6 CALL_FUNCTION 1
9 RETURN_VALUE
>>> dis.dis(lambda: '%s' % 100000)
9 0 LOAD...
Alphabet range in Python
...gt;>> string.ascii_lowercase
'abcdefghijklmnopqrstuvwxyz'
If you really need a list:
>>> list(string.ascii_lowercase)
['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
And to do it with range
>&g...