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Dynamically select data frame columns using $ and a character value

...is a reproducible example below: # set seed for reproducibility set.seed(123) df <- data.frame( col1 = sample(5,10,repl=T) , col2 = sample(5,10,repl=T) , col3 = sample(5,10,repl=T) ) # We want to sort by 'col3' then by 'col1' sort_list <- c("col3","col1") # Use 'do.call' to call order. S...
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Converting String to Int with Swift

... swift 4.0 let stringNumber = "123" let number = Int(stringNumber) //here number is of type "Int?" //using Forced Unwrapping if number != nil { //string is converted to Int } you could also use Optional Binding other than forced binding. eg...
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Why does the C preprocessor interpret the word “linux” as the constant “1”?

...le names like unix and assumed that programmers would simply avoid using those names for their own purposes. The 1989 ANSI C standard introduced rules restricting what symbols an implementation could legally predefine. A macro predefined by the compiler could only have a name starting with two unde...
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How to compare two floating point numbers in Bash?

...result back to the shell in a proper, machine-readable way. if awk -v n1="123.456" -v n2="3.14159e17" 'BEGIN { exit (n1 <= n2) }' /dev/null; then echo bigger; else echo not; fi ... though note how the condition is inverted (the exit status 0 means success to the shell). – t...
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Getting MAC Address

I need a cross platform method of determining the MAC address of a computer at run time. For windows the 'wmi' module can be used and the only method under Linux I could find was to run ifconfig and run a regex across its output. I don't like using a package that only works on one OS, and parsing ...
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ASP.NET Identity reset password

...();//"<YourLogicAssignsRequestedUserId>"; String newPassword = "test@123"; //"<PasswordAsTypedByUser>"; String hashedNewPassword = UserManager.PasswordHasher.HashPassword(newPassword); ApplicationUser cUser = await store.FindByIdAsync(userId); await store.SetPasswordH...
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How to list the size of each file and directory and sort by descending size in Bash?

... sort -h only works on GNU's version / Linux, no luck with BSD / OS X. – djule5 Sep 4 '15 at 20:14 add a comment  |  ...
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How to stop/terminate a python script from running?

... Is it possible to resume the script after stopping it? – Gathide Sep 7 '18 at 12:09 8 ...
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Convert a number range to another range, maintaining ratio

...edited Dec 16 '14 at 5:02 Rizier123 55k1616 gold badges7777 silver badges119119 bronze badges answered Dec 16 '14 at 4:40 ...
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Disabled form inputs do not appear in the request

...;form action="/Media/Add"> <input type="hidden" name="Id" value="123" /> <input type="textbox" name="Percentage" value="100" readonly/> </form> share | improve this ans...