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Remove duplicated rows using dplyr
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Note: dplyr now contains the distinct function for this purpose.
Original answer below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and...
How to forward declare a template class in namespace std?
and used that function in my main. I get errors. Of course, I know that there are more template params for std::list (allocator I think). But, that is beside the point. Do I have to know the full template declaration of a template class to be able to forward declare it?
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convert pfx format to p12
I need to export a .pfx format certificate (from windows mmc) to .p12 to use in another application. I cant find a way to do this. Can anyone suggest a method?
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How to add “on delete cascade” constraints?
... ON DELETE CASCADES to the both foreign keys in the following table without dropping the latter?
3 Answers
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Catching all javascript unhandled exceptions
I'm trying to find or figure out a way to display in an alert box all of the unhandled javascript exceptions in an application. I'd want all of this to be done on the client side, without using any server side code. I'm using MVC3 as an environment.
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How can I have two fixed width columns with one flexible column in the center?
I'm trying to set up a flexbox layout with three columns where the left and right columns have a fixed width, and the center column flexes to fill the available space.
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Rails nested form with has_many :through, how to edit attributes of join model?
How do you edit the attributes of a join model when using accepts_nested_attributes_for?
3 Answers
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Can I call memcpy() and memmove() with “number of bytes” set to zero?
Do I need to treat cases when I actully have nothing to move/copy with memmove() / memcpy() as edge cases
2 Answers
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Initializing a member array in constructor initializer
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How can I do what I want to do (that is, initialize an array in a constructor (not assigning elements in the body)). Is it even possible?
Yes. It's using a struct that contains an array. You say you already know about that, but then I don't understand the question. That way, you do initiali...
How to iterate over the keys and values in an object in CoffeeScript?
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Use for x,y of L. Relevant documentation.
ages = {}
ages["jim"] = 12
ages["john"] = 7
for k,v of ages
console.log k + " is " + v
Outputs
jim is 12
john is 7
You may also want to consider the variant for own k,v of ag...