大约有 4,100 项符合查询结果（耗时：0.0118秒） [XML]
Numbering rows within groups in a data frame
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Use ave, ddply, dplyr or data.table:
df$num <- ave(df$val, df$cat, FUN = seq_along)
or:
library(plyr)
ddply(df, .(cat), mutate, id = seq_along(val))
or:
library(dplyr)
df %>% group_by(cat) %>% mutate(id = row_number())
or (the most memory efficient, as it assigns by reference w...
Place cursor at the end of text in EditText
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There is a function called append for ediitext which appends the string value to current edittext value and places the cursor at the end of the value.
You can have the string value as the current ediitext value itself and call append();...
Finding all objects that have a given property inside a collection [duplicate]
...st for the Matchers. Some will argue that this is not Java-style, but it's fun how this guy twisted Java to make a bit of functional programming. Have a look at the source code also, it's quite sci-fi.
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How do I get the base URL with PHP?
...ERVER predefined variable.
If you plan on using https, you can use this:
function url(){
return sprintf(
"%s://%s%s",
isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] != 'off' ? 'https' : 'http',
$_SERVER['SERVER_NAME'],
$_SERVER['REQUEST_URI']
);
}
echo url();
#=> htt...
How to make gradient background in android
...a drawable .xml file, copy & paste the above code into this file, fave fun. <RelativeLayout ... android:background="@drawable/your_xml_name" ... >
– TomeeNS
Oct 3 '15 at 19:30
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Store password in TortoiseHg
... (not all development is open source), and having it stolen is not always fun.
– max
Sep 12 '12 at 23:07
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Find index of last occurrence of a sub-string using T-SQL
...ng using SQL? I am using SQL Server 2000 right now. I basically need the functionality that the .NET System.String.LastIndexOf method provides. A little googling revealed this - Function To Retrieve Last Index - but that does not work if you pass in a "text" column expression. Other solution...
AngularJS ui-router login authentication
... answered Mar 20 '14 at 15:53
CétiaCétia
12.4k44 gold badges5454 silver badges7979 bronze badges
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CSS opacity only to background color, not the text on it? [duplicate]
...use a transparent background, in which case you could try using the rgba() function:
rgba(R, G, B, A)
R (red), G (green), and B (blue) can be either <integer>s or <percentage>s, where the number 255 corresponds to 100%. A (alpha) can be a <number> between 0 and 1, or a <percent...
CMake link to external library
...nswered May 11 '12 at 11:19
AndréAndré
15.3k55 gold badges5151 silver badges6868 bronze badges
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