R help - Dec 2022 - lattice: how to use a log scale on the x-axis with the bwplot function

Dear R-Help list,

 ?? I would like to use bwplot from the lattice package with a log scale 
both on
the x-axis and the y-axis but I do not know how to do that because I do 
not know
how to change the factor x-axis in a numeric x-axis.

 ?Here is my example:


library(lattice)

# the mock data
y <- runif(100000,min=0, max=500)
x <- seq(0,500,length=length(y))
# I cut the x variable to create a factor variable in order to calculate 
the boxes
groups <- cut(x,10,ordered_result = TRUE)
# creating the dataframe for the lattice functions
DF <- data.frame( x= x , y = y, groups = groups)


## ok for xyplot
xyplot(?? y ~ x
 ????????? , data=DF
 ????????? , scales = list(
 ??????????? y = list(log=T)
 ??????????? , x = list(log=T)

 ????????? )
)

## ok for bwplot with the log scale for the y-axis
bwplot( y ~ groups
 ????????? , data=DF
 ????????? , scales = list(
 ??????????? y = list(log=T)
 ??????????? #???? , x = list(log=T)

 ????????? )
)



## Non ok for bwplot with the log scale for the x-axis
bwplot( y ~ groups
 ??????? , data=DF
 ??????? , scales = list(
 ????????????? y = list(log=T)
 ??????????? , x = list(log=T)

 ??????? )
)
which gives an error because the x-axis is a factor, I would like to 
replace it
for the display by the meddle of every class for example and put a log 
scale on the x-axis.

Thank you for your help
Best regards
Laurent



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Log-scales for the "factor" variable in bwplot() is not allowed.

You could, however, use the panel function panel.bwplot() with
xyplot(num ~ num). The potential problem with that is the box widths,
which panel.bwplot() will not know how to compute.

See if the following gives you a reasonable starting point:

DF <- within(DF, m <- tapply(y, groups, mean))
xyplot(y ~ m, DF, scales = list(log = TRUE),
       panel = panel.bwplot, horizontal = FALSE,
       box.width = .0001)

Best,
-Deepayan

On Sat, Dec 10, 2022 at 7:46 PM Laurent Rhelp <LaurentRHelp at free.fr>
wrote:
>
> Dear R-Help list,
>
>     I would like to use bwplot from the lattice package with a log scale
> both on
> the x-axis and the y-axis but I do not know how to do that because I do
> not know
> how to change the factor x-axis in a numeric x-axis.
>
>   Here is my example:
>
>
> library(lattice)
>
> # the mock data
> y <- runif(100000,min=0, max=500)
> x <- seq(0,500,length=length(y))
> # I cut the x variable to create a factor variable in order to calculate
> the boxes
> groups <- cut(x,10,ordered_result = TRUE)
> # creating the dataframe for the lattice functions
> DF <- data.frame( x= x , y = y, groups = groups)
>
>
> ## ok for xyplot
> xyplot(   y ~ x
>            , data=DF
>            , scales = list(
>              y = list(log=T)
>              , x = list(log=T)
>
>            )
> )
>
> ## ok for bwplot with the log scale for the y-axis
> bwplot( y ~ groups
>            , data=DF
>            , scales = list(
>              y = list(log=T)
>              #     , x = list(log=T)
>
>            )
> )
>
>
>
> ## Non ok for bwplot with the log scale for the x-axis
> bwplot( y ~ groups
>          , data=DF
>          , scales = list(
>                y = list(log=T)
>              , x = list(log=T)
>
>          )
> )
> which gives an error because the x-axis is a factor, I would like to
> replace it
> for the display by the meddle of every class for example and put a log
> scale on the x-axis.
>
> Thank you for your help
> Best regards
> Laurent
>
>
>
> --
> Cet e-mail a ?t? v?rifi? par le logiciel antivirus d'Avast.
> www.avast.com
>
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