[R] Integration + Normal Distribution + Directory Browsing Processing Questions

[Matthias Kohl]

Hi,

why don't you use pnorm?
E.g.,

pnorm(1, mean = 0.1, sd = 1.2) - pnorm(0, mean = 0.1, sd = 1.2)

Matthias

----- original message --------

Subject: Re: [R] Integration + Normal Distribution + Directory Browsing Processing Questions
Sent: Sun, 21 Jan 2007
From: Dimitris Rizopoulos<Dimitris.Rizopoulos at med.kuleuven.be>

> you can use the `...' argument of integrate, e.g.,
> 
> integrate(dnorm, 0, 1)
> integrate(dnorm, 0, 1, mean = 0.1)
> integrate(dnorm, 0, 1, mean = 0.1, sd = 1.2)
> 
> look at ?integrate for more info.
> 
> I hope it helps.
> 
> Best,
> Dimitris
> 
> ----
> Dimitris Rizopoulos
> Ph.D. Student
> Biostatistical Centre
> School of Public Health
> Catholic University of Leuven
> 
> Address: Kapucijnenvoer 35, Leuven, Belgium
> Tel: +32/(0)16/336899
> Fax: +32/(0)16/337015
> Web: http://med.kuleuven.be/biostat/
>       http://www.student.kuleuven.be/~m0390867/dimitris.htm
> 
> 
> Quoting Nils Hoeller <mail at nhoeller.de>:
> 
> > Hi everyone,
> >
> > I am new to R, but it's really great and helped me a lot!
> >
> > But now I have 2 questions. It would be great, if someone can help me:
> >
> > 1. I want to integrate a normal distribution, given a median and sd.
> > The integrate function works great BUT the first argument has to be a
> > function
> >
> > so I do integrate(dnorm,0,1) and it works with standard m. and sd.
> >
> > But I have the m and sd given.
> >
> > So for fixed m and sd I work around with a new function mynorm
> >
> > mynorm <- function(n) {
> >     ret <- dnorm(n,0.6,0.15)
> >     ret
> > }
> >
> > for example.
> >
> > BUT what can I do for dynamic m and sd?
> > I want something like integrate(dnorm(,0.6,0.15),0,1), with the first
> > dnorm parameter open for the
> > integration but fixed m and sd.
> >
> > I hope you can help me.
> >
> > 2. I am working with textfiles with rows of measure data.
> > read.table("file") works fine.
> >
> > Now I want R to read.table all files within a given directory and
> > process them one by the other.
> >
> > for(all files in dir xy) {
> > x <- read.table(nextfile)
> > process x
> > }
> >
> > Is that possible with R? I hope so. Can anyone give me a link to
> examples.
> >
> > Thanks for your help
> >
> > Nils
> >
> > ______________________________________________
> > R-help at stat.math.ethz.ch mailing list
> > https://stat.ethz.ch/mailman/listinfo/r-help
> > PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.
> >
> >
> 
> 
> 
> Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
> 

--- original message end ----


--
Dr. rer. nat. Matthias Kohl
Matthias.Kohl at stamats.de
www.stamats.de