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Creating an instance of class
What's the difference between lines 1 , 2 , 3 , 4?
3 Answers
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Integrate ZXing in Android Studio
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I was integrating ZXING into an Android application and there were no good sources for the inpu...
Does a C# app track how long its been running?
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How to remove last n characters from every element in the R vector
...rame("data"=char_array,"data2"=1:4)
a$data = substr(a$data,1,nchar(a$data)-3)
a should now contain:
data data2
1 foo_ 1
2 bar_ 2
3 ap 3
4 b 4
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R - Concatenate two dataframes?
...olumn b to data frame b.
Results
> a <- data.frame(a=c(0,1,2), b=c(3,4,5), c=c(6,7,8))
> a
a b c
1 0 3 6
2 1 4 7
3 2 5 8
> b <- data.frame(a=c(9,10,11), c=c(12,13,14))
> b
a c
1 9 12
2 10 13
3 11 14
> b$b <- NA
> b
a c b
1 9 12 NA
2 10 13 NA
3 11 14 NA
> ...
Pandas dataframe get first row of each group
...;> df.groupby('id').first()
value
id
1 first
2 first
3 first
4 second
5 first
6 first
7 fourth
If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6...
ASP.NET MVC 3 Razor: Include JavaScript file in the head tag
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399
You can use Named Sections.
_Layout.cshtml
<head>
<script type="text/javascript...
rails 3 validation on uniqueness on multiple attributes
I use Rails 3.0.0.beta4
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