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How to reshape data from long to wide format

...mes(df) <- unique(dat1$name) df sqldf package: library(sqldf) sqldf('SELECT name, MAX(CASE WHEN numbers = 1 THEN value ELSE NULL END) x1, MAX(CASE WHEN numbers = 2 THEN value ELSE NULL END) x2, MAX(CASE WHEN numbers = 3 THEN value ELSE NULL END) x3, MAX(CASE WHEN numbe...
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Trimming a huge (3.5 GB) csv file to read into R

... My try with readLines. This piece of a code creates csv with selected years. file_in <- file("in.csv","r") file_out <- file("out.csv","a") x <- readLines(file_in, n=1) writeLines(x, file_out) # copy headers B <- 300000 # depends how large is one pack while(length(x)) { ...
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Check if one IEnumerable contains all elements of another IEnumerable

... bool result; //Get the value var list1WithValue = list1.Select(s => s.Value).ToList(); var list2WithValue = list2.Select(s => s.Value).ToList(); result = !list1WithValue.Except(list2WithValue).Any(); return result; } ...
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Split output of command by columns using Bash?

...d> | while read a b; do echo $a; done The first parameter to read, a, selects the first column, and if there is more, everything else will be put in b. As a result, you never need more variables than the number of your column +1. So, while read a b c d; do echo $c; done will then output th...
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Pass a data.frame column name to a function

...(x[,column]) } fun1(df, "B", max) Alternatively, using [[ also works for selecting a single column at a time: df <- data.frame(A=1:10, B=2:11, C=3:12) fun1 <- function(x, column){ max(x[[column]]) } fun1(df, "B") ...
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Segue to another storyboard?

...; // Load the initial view controller from the storyboard. // Set this by selecting 'Is Initial View Controller' on the appropriate view controller in the storyboard. UIViewController *theInitialViewController = [secondStoryBoard instantiateInitialViewController]; // // **OR** // // Load the view...
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how to ignore namespaces with XPath

... You can use the local-name() XPath function. Instead of selecting a node like /path/to/x:somenode you can select all nodes and filter for the one with the correct local name: /path/to/*[local-name() = 'somenode'] ...
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RegEx: Grabbing values between quotation marks

... Please, why this works? I was using src="(.*)" but obviously it was selecting everything before the last ", your REGEX, though, selected only the src="" contents, but I didn't understand how? – Lucas Bustamante Jul 25 '18 at 23:25 ...
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Cannot open backup device. Operating System error 5

... Go to the SQL server folder in start menu and click configuration tools Select SQL Server configuration manager On SQL server services, on the desired instance change the (Log On as) to local system share | ...
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Is it possible to download an old APK for my app from Google Play?

... releases => Production (Manage Production) => Release history => Select the version that you want => Click on Download button. Your account should be granted with full permissions, otherwise the download button will be hidden. Original Answer Go to Developer Console => Ma...