R help - Jan 2007 - Integration + Normal Distribution + Directory Browsing Processing Questions

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

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

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

On Jan 21, 2007, at 2:27 PM, Nils Hoeller wrote:
> Now I want R to read.table all files within a given directory and
> process them one by the other.
?list.files
?"for"

Haris

Hi Nils,

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

Best,
Matthias

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

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

Nils Hoeller wrote:
> 
> 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.
integrate(function(x)dnorm(x,0.1,1.2), 0, 1)
is a way of "fixing" additional parameters.



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