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How to output only captured groups with sed?
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answered May 6 '10 at 2:39
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Extract first item of each sublist
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201
Using list comprehension:
>>> lst = [['a','b','c'], [1,2,3], ['x','y','z']]
>>&...
How can I convert a DateTime to the number of seconds since 1970?
...ateTime variable to Unix time, ie, the number of seconds since Jan 1st, 1970. It looks like a DateTime is actually implemented as the number of 'ticks' since Jan 1st, 0001.
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Python 3.x rounding behavior
I was just re-reading What’s New In Python 3.0 and it states:
11 Answers
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Why does (0 < 5 < 3) return true?
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Order of operations causes (0 < 5 < 3) to be interpreted in javascript as ((0 < 5) < 3) which produces (true < 3) and true is counted as 1, causing it to return true.
This is also why (0 < 5 < 1) returns false, (0 < 5) returns t...
Razor HtmlHelper Extensions (or other namespaces for views) Not Found
...r.Configuration.RazorWebSectionGroup, System.Web.WebPages.Razor, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
<section name="host" type="System.Web.WebPages.Razor.Configuration.HostSection, System.Web.WebPages.Razor, Version=1.0.0.0, Culture=neutral, PublicKeyToken=3...
“CASE” statement within “WHERE” clause in SQL Server 2008
...ery which contains "CASE" statement within "WHERE" clause. But SQL Server 2008 is giving some errors while executing it. Can anyone please help me with the correct query? Here is the query:
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How to check whether a pandas DataFrame is empty?
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505
You can use the attribute df.empty to check whether it's empty or not:
if df.empty:
print(...
Simplest way to profile a PHP script
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104
The PECL APD extension is used as follows:
<?php
apd_set_pprof_trace();
//rest of the scri...
MongoDB sort排序、index索引教程 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...果。
实例
col 集合中的数据如下：
{ "_id" : ObjectId("56066542ade2f21f36b0313a"), "title" : "PHP 教程", "description" : "PHP 是一种创建动态交互性站点的强有力的服务器端脚本语言。", "by" : "菜鸟教程", "url" : "https://www.tsingfun.com", "tags" : [ "php"...