大约有 48,000 项符合查询结果（耗时：0.0544秒） [XML]
Extract a regular expression match
...nd adds a few that are missing:
library(stringr)
str_locate("aaa12xxx", "[0-9]+")
# start end
# [1,] 4 5
str_extract("aaa12xxx", "[0-9]+")
# [1] "12"
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JavaScript + Unicode regexes
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205
Situation for ES 6
The upcoming ECMAScript language specification, edition 6, includes Unicode-...
std::function vs template
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answered Feb 3 '13 at 22:50
Andy ProwlAndy Prowl
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Mixed mode assembly is built against version ‘v2.0.50727′ of the runtime
...yV2RuntimeActivationPolicy="true">
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/>
<requiredRuntime version="v4.0.20506" />
</startup>
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Defining a percentage width for a LinearLayout? [duplicate]
I want to define a percentage width (70%) for a LinearLayout that contains some buttons, so that I can center it and so that the child buttons can fill_parent. Here's a picture showing what I mean:
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Add 2 hours to current time in MySQL?
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edited Aug 20 '13 at 7:23
answered Feb 26 '09 at 8:41
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Using awk to print all columns from the nth to the last
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will print all but very first column:
awk '{$1=""; print $0}' somefile
will print all but two first columns:
awk '{$1=$2=""; print $0}' somefile
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Python's “in” set operator
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101
Yes, but it also means hash(b) == hash(x), so equality of the items isn't enough to make them t...
Position Absolute + Scrolling
...s:
.inner: { position: relative; height: auto; }
.full-height: { height: 100%; }
Setting the inner div's position to relative makes the absolutely position elements inside of it base their position and height on it rather than on the .container div, which has a fixed height. Without the inner, re...
Postgresql aggregate array
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Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need to repeat the columns on SELECT to G...