Practice - Create a Function
What is Function ?
A function is a set of statements organized together to perform a specific task
ex: mean() (arithmetic mean)
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Create a Function
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Create a Function
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Create a Function
Problem: Take a sample belonged to population, and sum
box <- 1:6 # This is my population in a BOX
box
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samp <- sample(box, size = 2) # This is my sample, I choose two values.
samp
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Create a Function
I want to collect my sample() and sum() functions and put in ONE function. I will create a new function named roll2().
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name_new_function <- function( argument ) {
name_new_variable <- do_this( argument, option )
then_do_this( name_new_variable )
}
name_new_function( ) # It will work with my default argument
Create a Function
name_new_function <- function( argument ) {
name_new_variable <- do_this( argument, option )
then_do_this( name_new_variable )
}
name_new_function( ) # It will work with my default argument
in formal :
roll2 <- function(box = 1:6) {
samp <- sample(box, size=2)
sum(samp)
}
roll2( ) # It will work with my default argument ( box = 1:6 )
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Create a Function
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roll2 <- function(box = 1:6) {
samp <- sample(box, size=2)
sum(samp)
}
roll2() # It will work with my default argument ( box = 1:6 )
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Create a Function
You can change the default argument in every time
roll2(box = 1:10) # It will work with argument ( 1,2,3,4,5,6,7,8,9,10 )
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roll2(1:10) # It will work with argument ( 1,2,3,4,5,6,7,8,9,10 )
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roll2(seq(1,10,0.5)) # It will work with argument ( 1, 1.5, 2, 2.5, 3,... )
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Practice - Create a Function
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You can add new options or new functions in your new function.
{ } and () are important
# Think about these functions
# mean(), print(), plot(), max(), install.packages(), help(), ...
Extended Syllabus PDF
Check, Conditions and Loops, DataCamp