There may be more concise ways to do this - but you are 99% there with your
approach:
try:
boxplot(mydata[,names(sort(apply(mydata,2,median)))])
B.
On Mar 21, 2015, at 6:49 PM, Antonio Silva <aolinto....@gmail.com> wrote:
> Thanks Bill and David
>
> Here goes an example
>
> SP1<-c(9,6,7,8,5,8,7,5,9,7)
> SP2<-c(1,3,4,2,4,2,5,3,2,1)
> SP3<-c(4,6,7,5,7,8,7,6,5,4)
> SP4<-c(5,4,3,5,2,3,4,3,4,2)
> mydata<-data.frame(SP1,SP2,SP3,SP4)
> rownames(mydata)<-c("ST1","ST2","ST3","ST4","ST5","ST6","ST7","ST8","ST9","ST10")
> mydata
> boxplot(mydata)
>
> Note that this data frame does not have the format Response ~ Group. In my
> real matrix I have up to 40 species.
>
> Is there any way to have the species ordered by their median abundance (or
> other parameter?)
>
> The desired order is given by names(sort(apply(mydata,2,median)))
>
> Thanks once more,
>
> Antonio Olinto
> Fisheries Institute
> Sao Paulo, Brazil
>
> 2015-03-21 15:13 GMT-03:00 William Dunlap <wdun...@tibco.com>:
>
>> You can use the reorder() function to reorder the grouping vector's
>> factor levels according to a function of the data in each group. E.g.,
>> compare the following two plots:
>>
>> d <- data.frame(Response=cos(1:15), Group=rep(c("A","B","C"),c(6,5,4)))
>> par(mfrow=c(1,2))
>> boxplot(Response ~ Group, data=d)
>> boxplot(Response ~ reorder(Group, X=Response, FUN=median), data=d)
>>
>>
>> Bill Dunlap
>> TIBCO Software
>> wdunlap tibco.com
>>
>> On Fri, Mar 20, 2015 at 2:20 PM, Antonio Silva <aolinto....@gmail.com>
>> wrote:
>>
>>> Hello
>>>
>>> I'm using a dataframe (mydata) where row names are sampling points and
>>> column names are species in a multivariate analysis.
>>>
>>> If I write boxplot(mydata) I'll have boxplots for each species abundance
>>> in
>>> alphabetical order.
>>>
>>> How to get the boxes orderer by the median?
>>>
>>> Usually for this I write
>>>
>>> boxplot(value~category,at=rank(tapply(mydata$value,mydata$category,median)))
>>> but for this to work I need a column for the categories and another column
>>> for the values.
>>>
>>> Thanks in advance, best regards.
>>>
>>> Antonio Olinto
>>>
>>> [[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.
>>>
>>
>>
>
> [[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.
______________________________________________
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.
