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Using R to download zipped data file, extract, and import data

... Zip archives are actually more a 'filesystem' with content metadata etc. See help(unzip) for details. So to do what you sketch out above you need to Create a temp. file name (eg tempfile()) Use download.file() to fetch the file into the temp....
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Unique constraint on multiple columns

...ied from technet's documentation, is in the form of: CONSTRAINT constraint_name UNIQUE [ CLUSTERED | NONCLUSTERED ] ( column [ ASC | DESC ] [ ,...n ] ) Therefore, the resuting table definition would be: CREATE TABLE [dbo].[user]( [userID] [int] IDENTITY(1,1) NOT NULL, [fcode] [int] ...
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PHP foreach change original array values

...lt;= 0) { $fields[$key]['value'] = "Some error"; } } So basically use $field when you need the values, and $fields[$key] when you need to change the data. share | improve this answer ...
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Best way to find the intersection of multiple sets?

... want here, but in case you ever need a generalisation of "take the sum of all these", "take the product of all these", "take the xor of all these", what you are looking for is the reduce function: from operator import and_ from functools import reduce print(reduce(and_, [{1,2,3},{2,3,4},{3,4,5}]))...
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Android studio - Failed to find target android-18

... I think you might not have the Android-18 sdk installed. Go to Tools > Android > SDK Manager and check to see if Android 4.3 (API 18) is installed. share | improve thi...
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Xcode stuck at “Your application is being uploaded”

... just keep your head cool and check this first method: Check if your firewall protection is off. If not then turn it off. It maybe blocking you to connect your computer with iTunes Store. Try a different internet connection. The purpose for trying a different internet connection is that your curre...
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How do I create directory if none exists using File class in Ruby?

...added a core-only solution to my answer: Be aware, however, that it essentially reimplements FileUtils.mkdir_p (which is the method dedicated to your use case) – Eureka Sep 27 '12 at 9:12 ...
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Can not connect to local PostgreSQL

... This really looks like a file permissions error. Unix domain sockets are files and have user permissions just like any other. It looks as though the OSX user attempting to access the database does not have file permissions to acce...
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Signed to unsigned conversion in C - is it always safe?

...herwise, if the type of the operand with signed integer type can represent all of the values of the type of the operand with unsigned integer type, then the operand with unsigned integer type is converted to the type of the operand with signed integer type. Otherwise, both operands are converted t...
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Is there any publicly accessible JSON data source to test with real world data? [closed]

..., for example - A GET request to: https://api.twitter.com/1/statuses/user_timeline.json?include_entities=true&include_rts=true&screen_name=mralexgray&count=1, EDIT: Removed due to twitter restricting their API with OAUTH requirements... {"errors": [{"message": "The Twitter REST API...