[R] plot is not keeping the order of variable

[Peter Dalgaard]

Or Duek wrote:
> Ok,
> It seems that the problem lays in the order (as Ista mentioned),
> But, when I ask R to order it he chooses to order it by size and not by the
> specific order I mentioned when I built the vector.
> Is it possible to tell him to keep the order as mentioned?
> Thank you.

You're still not completely clear about how you built the factor, but I 
venture a guess:

Notice that factors tend to get their levels in alphabetical order, 
unless special tricks are used.

 > d <- data.frame(f=c("rare", "medium","well-done"))
 > d$f
[1] rare      medium    well-done
Levels: medium rare well-done

To get the cast in order of appearance, this can be used:

 > d$f <- factor(d$f, levels=unique(d$f))
 > d$f
[1] rare      medium    well-done
Levels: rare medium well-done


> 
> 
> On Sun, Feb 21, 2010 at 6:16 PM, Ista Zahn <istazahn at gmail.com> wrote:
> 
>> Hi Or,
>> I can't know for sure what your problem is without an example, but the
>> first thing I would do is check to make sure that your labels are
>> stored as an ordered factor (and that the order is correct). See
>> ?factor for details.
>>
>> Best,
>> Ista
>>
>> On Sun, Feb 21, 2010 at 10:57 AM, Or Duek <orduek at gmail.com> wrote:
>>> Hi,
>>> I created a simple data frame with one factor and one numerical variable.
>>> The factor was actually a vector of names of techniques to trimm reaction
>>> time data.
>>> I want to create a plot that shows the value of F test for every trimming
>>> method.
>>> So the data frame has its trim factor (who has those labels
>>> "mean","2500","2000","1500","1000","log","inverse","1SD","2SD")
>>> and the numerical variable of the data frame has the F values for each
>> one
>>> of those trimming method.
>>> When I ask R to plot it, it doesn't keep the order of the trimm verctor
>>> correctly and the plot confuses the order so the most left one will be
>> 1500
>>> and then 1SD etc.
>>> The values are correct but it is important for me to keep it in the same
>>> order I built it.
>>> How can I do it?
>>> Thank you very much,
>>> Or D.
>>>
>>>        [[alternative HTML version deleted]]
>>>
>>> ______________________________________________
>>> R-help at r-project.org 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.
>>>
>>
>>
>> --
>> Ista Zahn
>> Graduate student
>> University of Rochester
>> Department of Clinical and Social Psychology
>> http://yourpsyche.org
>>
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at r-project.org 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.


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    O__  ---- Peter Dalgaard             Øster Farimagsgade 5, Entr.B
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