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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...
Converting String to Int with Swift
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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...
A Windows equivalent of the Unix tail command [closed]
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I'd suggest installing something like GNU Utilities for Win32. It has most favourites, including tail.
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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...
Wait for a process to finish
...ed Jan 12 '17 at 12:41
Rauno PalosaariRauno Palosaari
1,51911 gold badge88 silver badges55 bronze badges
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Unable to execute dex: GC overhead limit exceeded in Eclipse
When I downloaded the Git project OsmAnd and went to compile it,
Eclipse returned these errors:
9 Answers
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Can you make valid Makefiles without tab characters?
On my system (Mac OS X), make seems to require that that Makefiles have a tab character preceding the the content of each command line, or it throws a syntax error.
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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...
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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Best practice to run Linux service as a different user
... my RHEL box. If I recall correctly, the same is true for other Linux distros which use the init scripts in /etc/init.d .
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