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On localhost, how do I pick a free port number?
...do I figure out which port is available? I assume I cannot listen on port 80 or 21?
5 Answers
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MySQL - Rows to Columns
...temvalue |
+--------+----------+-----------+
| 1 | A | 10 |
| 1 | B | 3 |
| 2 | A | 9 |
| 2 | C | 40 |
+--------+----------+-----------+
This will be our goal, the pretty pivot table:
select * from history_itemvalue_piv...
How to access pandas groupby dataframe by key
...group method:
In [21]: gb.get_group('foo')
Out[21]:
A B C
0 foo 1.624345 5
2 foo -0.528172 11
4 foo 0.865408 14
Note: This doesn't require creating an intermediary dictionary / copy of every subdataframe for every group, so will be much more memory-efficient that creating...
Shuffle two list at once with same order
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– Jaroslav Klimčík
Apr 25 '14 at 10:15
4
(noob question) - what does the * mean?
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Regex how to match an optional character
...e letter optional. {1} is redundant. (Of course you could also write [A-Z]{0,1} which would mean the same, but that's what the ? is there for.)
You could improve your regex to
^([0-9]{5})+\s+([A-Z]?)\s+([A-Z])([0-9]{3})([0-9]{3})([A-Z]{3})([A-Z]{3})\s+([A-Z])[0-9]{3}([0-9]{4})([0-9]{2})([0-9]{2})
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Join a list of strings in python and wrap each string in quotation marks
...ords = ['hello', 'world', 'you', 'look', 'nice']
>>> ', '.join('"{0}"'.format(w) for w in words)
'"hello", "world", "you", "look", "nice"'
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top命令使用详解 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...信息，同 uptime 命令的执行结果。其内容如下：
01:06:48
当前时间
up 17 days, 6:21
系统运行时间，格式为时:天数，小时:分钟
1 user
当前登录用户数
load average: 0.05, 0.08, 0.03
系统负载，即任务队列的平...
What's quicker and better to determine if an array key exists in PHP?
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10 Answers
10
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Force page scroll position to top at page refresh in HTML
... method on DOM ready:
$(document).ready(function(){
$(this).scrollTop(0);
});
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