Re: [R] cdf in R give probability of random variable

2016-10-22 Thread Martin Maechler 
> peter dalgaard 
> on Fri, 21 Oct 2016 22:10:22 +0200 writes:

>> On 21 Oct 2016, at 20:23 , peter dalgaard
>>  wrote:
>> 
>> In both cases it works out nicer if you do
>> 
>> names(px) <- x
>> barplot(px)

> Um, unless of course you want the cdf as a step function,
> in which case check the help page for plot for possible
> values of the type= argument.

and if it is not homework, (or even then ;-)  just use

  plot(ecdf(x))


Martin Maechler, ETH Zurich

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.

Re: [R] cdf in R give probability of random variable

2016-10-21 Thread peter dalgaard 

> On 21 Oct 2016, at 20:23 , peter dalgaard  wrote:
> 
> In both cases it works out nicer if you do
> 
> names(px) <- x
> barplot(px)
> 

Um, unless of course you want the cdf as a step function, in which case check 
the help page for plot for possible values of the type= argument.

-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Office: A 4.23
Email: pd@cbs.dk  Priv: pda...@gmail.com

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.

Re: [R] cdf in R give probability of random variable

2016-10-21 Thread peter dalgaard 
This looks like homework, but doing it in R might not be, so I'll give you the 
benefit of doubt...


> On 21 Oct 2016, at 18:30 , Ragia .  wrote:
> 
> 
> Dear Grooup
> 
> kindly
> 
> how can I plot  these  graphs in R..
> 
> 
> Suppose that X is a discrete random variable with P(X = 0) = .25, P(X = 1) =
> .125, P(X = 2) = .125, and P(X = 3) = .5. Graph the frequency function and
> the cumulative distribution function of X.
> 
> 
> 
> my solution was:
> 
> x=c(0,1,3)
> px=c(.25,.125,.5)
> plot( x,px ,type="h"  ) # to plot the frequency  , is it correct
> 

You forgot X=2 in there (check the sum). 

> how to plot the cdf?
> 

cumsum() is your friend.

In both cases it works out nicer if you do

names(px) <- x
barplot(px)

-pd

>   [[alternative HTML version deleted]]

Notice that plain text posting is strongly preferred in here. HTML messes up 
code badly sometimes.

-- 
Peter Dalgaard, Professor,
Center for Statistics, Copenhagen Business School
Solbjerg Plads 3, 2000 Frederiksberg, Denmark
Phone: (+45)38153501
Office: A 4.23
Email: pd@cbs.dk  Priv: pda...@gmail.com

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.

[R] cdf in R give probability of random variable

2016-10-21 Thread Ragia . 

Dear Grooup

kindly

how can I plot  these  graphs in R..


Suppose that X is a discrete random variable with P(X = 0) = .25, P(X = 1) =
.125, P(X = 2) = .125, and P(X = 3) = .5. Graph the frequency function and
the cumulative distribution function of X.



my solution was:

x=c(0,1,3)
px=c(.25,.125,.5)
plot( x,px ,type="h"  ) # to plot the frequency  , is it correct

 how to plot the cdf?



thanks in advance


Ragia



[[alternative HTML version deleted]]

__
R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
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.