Difference between readline() and scan() and how to use them - r

I have been tasked to use either the function readline() or scan() in my program, though the definitions in R Studio are vague and confusing for a beginner like me. Can someone please explain the main uses of these functions and how can I use them properly? Thank you!

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how to define variables after importing excel sheet in R

i imported exel to R now i do not know how to solve the question, as it is my 1st time with R
As this looks like an assignment/homework question, and you mention this is your 1st time with R, I think you would benefit more from looking at an in-depth introduction to R than a quick answer here. This site seems to be a good introduction: https://intro2r.com/index.html . The site recommend RStudio which is far more intuitive and easy to use than base R.
There is also often good documentation on basic functions within R itself. Type ? into the console before any command and it will direct you to some helpful information. For example, you may find these useful to get started.
?hist
?plot
?min
?max

erf() and IntervalRootFinding

I realize this is a pretty niche problem, but I figure it's worth asking anyway.
I'm working on a program that does root-finding, and the function that it's trying to find a root for involves computing Fresnel integrals, which are implemented using erf(). I thought I'd try using the IntervalRootFinding package, but haven't gotten very far with it. I get a MethodError exception, which looks like:
MethodError: no method matching _erf(::Complex{IntervalArithmetic.Interval{Float64}})
Any advice?
IntervalArithmatic requires that your functions know how to work with intervals. Since erf is monotonic, you could define your own implimentation
using IntervalArithmatic
erf(x::Interval{T}) where T = Interval(prevfloat(erf(x.lo)), nextfloat(erf(x.hi)))

Xap.require in R

I'm trying to work with this tutorial. I'm confused because in the very first line there is this code
xap.require('oro.dicom','oro.nifti')
but I cannot find any function called xap.require online or with ??. It seems like this is related to software developement. Does anyone have idea what this is for?
It would appear this is a peculiarity of ANALYTIXAGILITY. My guess is that they have their own package for integrating the R console into their platform.

R checkParams() function

Does anyone know if there is an R function called checkParams() and if so, could explain what it does? I found a checkParams function here, but I do not think this is the one being used by the code I am reading.

R template for evolutionary algorithms?

Is there a ready template to run evolutionary\genetic algorithms in R?
I am interested in a code that would allow me to add graphical output and user input between iterations.
Thanks for reading!
p.s. found this posting Is there any Genetic Programming code written R
I don't know about genetic programming code written in R, but there is a program called HeuristicLab you can use.
There you can add an External Evaluator in R code and there you can add your graphical output.
Here is a link on how to do it:
http://dev.heuristiclab.com/trac/hl/core/wiki/UsersHowtosOptimizingExternalApplications
Its an open source program and the staff that wrote it usually answers any question you have very quickly.
Here is the download page: http://dev.heuristiclab.com/trac/hl/core/wiki
good luck!
Yep, i think http://rsymbolic.org/projects/show/rgp is exactly what you're looking for.

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