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How to combine multiple conditions to subset a data-frame using “OR”?
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filter(df, v1 < 0.5 | v2 == "g")
Using sqldf:
library(sqldf)
sqldf('SELECT *
FROM df
WHERE v1 < 0.5 OR v2 = "g"')
Output for the above options:
v1 v2
1 0.26550866 a
2 0.37212390 b
3 0.20168193 e
4 0.94467527 g
5 0.06178627 j
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How to add http:// if it doesn't exist in the URL?
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This should be the selected answer - why roll your own when the language has native support? Nice work.
– Tom Auger
Aug 19 '13 at 15:24
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How to make a div with no content have a width?
...on, any padding greater than 0 will work. That way you don't have a weird, selectable &nbsp; in the div.
– Brian Duncan
Apr 12 '13 at 18:20
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Where does R store packages?
...rature. Once you find it, go to the /etc subdirectory.
C:\R\R-2.10.1\etc
Select the file in this folder named Rprofile.site. I open it with VIM. You will find this is a bare-bones file with less than 20 lines of code. I inserted the following inside the code:
# my custom library path
.libPaths("C...
How to map with index in Ruby?
...erator object (in 1.8.7+), which mixes in Enumerable, so you can call map, select, reject etc. on it just like on an array, hash, range etc.
– sepp2k
Jan 15 '11 at 1:45
9
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How to set MSDN to be always in English
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You can select your default language from bottom left of the page.
Edit
New docs site has an easier option to view in English. However, the setting is not permanent.
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How to pinch out in iOS simulator when map view is only a portion of the screen?
...ircles hovered over a table view on the bottom left causing the rows to be selected.
– Christopher
Jul 25 '12 at 22:08
2
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Parser for C#
...2 also shows how you can then use the information gathered from the AST to select on the source code a type, method, comment, etc..
For reference here is the API code that wrote (note that this is my first pass at using SharpDevelop's C# AST parser, and I am still getting my head around how it work...
Disable orange outline highlight on focus
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this should be the selected answer
– mlg87
Apr 16 '19 at 15:04
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MongoDb query condition on comparing 2 fields
...have a collection T , with 2 fields: Grade1 and Grade2 , and I want to select those with condition Grade1 > Grade2 , how can I get a query like in MySQL?
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