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

From: Matthias Kohl <Matthias.Kohl_at_stamats.de>
Date: Mon 22 Jan 2007 - 08:08:18 GMT


Hi Nils,

I would say, pnorm is faster and has a higher precision.

Best,
Matthias

Subject: Re: [R] Integration + Normal Distribution + Directory Browsing Processing Questions Sent: Mon, 22 Jan 2007
From: Nils Hoeller<mail@nhoeller.de>

> Thank you,
>
> both work fine. Why is pnorm to prefer?
>
> Nils
>
>
> Matthias Kohl schrieb:
> > 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@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@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@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@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@stamats.de
> > www.stamats.de
> >
> >
>
> ______________________________________________
> R-help@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.
>

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

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Received on Mon Jan 22 19:14:48 2007

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