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Extract a regular expression match
... use PERL regexs' lazy matching:
> sub(".*?([0-9]+).*", "\\1", "aaa12xx99",perl=TRUE)
[1] "12"
Trying to substitute out non-digits will lead to an error in this case.
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Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
... size_t with printf, you should use "%zu" if using the latest C standard (C99).
– Chris Young
Oct 3 '08 at 7:44
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How to get everything after last slash in a URL?
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Benjamin WohlwendBenjamin Wohlwend
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Cannot lower case button text in android studio
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Hai RomHai Rom
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Smarty中date_format日期格式化详解 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...间表达
%C - 世纪值（年份除以 100 后取整，范围从 00 到 99）
%d - 月份中的第几天，十进制数字（范围从 01 到 31）
%D - 和 %m/%d/%y 一样
%e - 月份中的第几天，十进制数字，一位的数字前会加上一个空格（范围从 ' 1' 到 '31'）
%g - ...
What are the Ruby Gotchas a newbie should be warned about? [closed]
...tors.
To denote floating point numbers, one must follow with a zero digit (99.0) or an explicit conversion (99.to_f). It is insufficient to append a dot (99.), because numbers are susceptible to method syntax.
Boolean evaluation of non-boolean data is strict: 0, "" and [] are all evaluated to true. ...
How to show Page Loading div until the page has finished loading?
...ed;
display: block;
opacity: 0.7;
background-color: #fff;
z-index: 99;
text-align: center;
}
#loading-image {
position: absolute;
top: 100px;
left: 240px;
z-index: 100;
}
Then, add this javascript to your page (preferably at the end of your page, before your closing </body>...
ImportError: No Module Named bs4 (BeautifulSoup)
...hi RajapakshaWimukthi Rajapaksha
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Sequence contains no elements?
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JoshJordan
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answered Aug 24 '09 at 19:23
Marc Gravell♦Marc G...
What's the difference between echo, print, and print_r in PHP?
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Pragnesh Chauhan
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answered Dec 13 '12 at 5:50
user1899888user1899888...