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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
...
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...
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...
Specifically, what's dangerous about casting the result of malloc?
... but forgetting to include stdlib.h. Compilers may assume that malloc is a function returning int, therefore converting the void* pointer actually returned by malloc to int and then to your pointer type due to the explicit cast. On some platforms, int and pointers may take up different numbers of by...
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
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answered Dec 16 '14 at 4:40
...
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>
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What is the single most influential book every programmer should read? [closed]
...tation
Writing Secure Code (2nd Edition) by Michael Howard
Introduction to Functional Programming by Philip Wadler and Richard Bird
No Bugs! by David Thielen
Rework by Jason Freid and DHH
JUnit in Action
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How can I change Eclipse theme?
... Theme" mentions this GitHub repo "eclipse themes - darker":
The big fun is that, the codes are minimized by using Eclipse4 platform technologies like dependency injection.
It proves that again, the concise codes and advanced features could be achieved by contributing or extending with the e...
Node.js or Erlang
...r learning curve, you will get more out of it since you will be learning a functional programming language. Also, since Erlang is specifically designed to create reliable, highly concurrent systems, you will learn plenty about creating highly scalable services at the same time.
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