[R] Coord_equal in ggplot2

[ONKELINX, Thierry]

Dear Dieter,

I tried that. But it rescales one of the axis. The resulting graph is
still square. But now 1 cm Y-axis equal 2.5 cm on the X-axis. This seems
not te be the documented behaviour. 

ggplot(ds, aes(x = x, y = y)) + geom_point() + coord_equal(ratio = 2/5) 

From sessionInfo()

R 2.9.0 on WinXP
ggplot2_0.8.3 reshape_0.8.3 plyr_0.1.8    proto_0.3-8

Regards,

Thierry


------------------------------------------------------------------------
----
ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature
and Forest
Cel biometrie, methodologie en kwaliteitszorg / Section biometrics,
methodology and quality assurance
Gaverstraat 4
9500 Geraardsbergen
Belgium
tel. + 32 54/436 185
Thierry.Onkelinx at inbo.be
www.inbo.be

To call in the statistician after the experiment is done may be no more
than asking him to perform a post-mortem examination: he may be able to
say what the experiment died of.
~ Sir Ronald Aylmer Fisher

The plural of anecdote is not data.
~ Roger Brinner

The combination of some data and an aching desire for an answer does not
ensure that a reasonable answer can be extracted from a given body of
data.
~ John Tukey

-----Oorspronkelijk bericht-----
Van: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
Namens Dieter Menne
Verzonden: dinsdag 19 mei 2009 16:15
Aan: r-help at stat.math.ethz.ch
Onderwerp: Re: [R] Coord_equal in ggplot2

ONKELINX, Thierry <Thierry.ONKELINX <at> inbo.be> writes:
> 
> I'm plotting some points on a graph where both axes need to have the 
> same scale. See the example below. Coord_equal does that trick but in 
> this case it wastes a lot of space on the y-axis. Setting the limits 
> of the y-axis myself was no avail.
> 
> Any suggestions to solve this problem?  
> 
> library(ggplot2)
> ds <- data.frame(x = runif(1000, min = 0, max = 300000), y = 
> runif(1000, min = 140000, max = 260000)) ggplot(ds, aes(x = x, y = y))

> + geom_point() + coord_equal() ggplot(ds, aes(x = x, y = y)) + 
> geom_point() + coord_equal() + scale_x_continuous(limits = c(0, 
> 300000)) + scale_y_continuous(limits = c(140000, 260000))

I think you need to set ratio in addition to cut off the extra space.
(Not tried)

>From Docs:

Equal scales. coord_equal ensures that the x and y axes have equal
scales: i.e.
1 cm along the x axis represents the same range of data as 1 cm along
the y axis. By default it will assume that you want a one-to-one ratio,
but you can change this with the ratio parameter. The aspect ratio will
also be set to ensure that the mapping is maintained regardless of the
shape of the output device. See the documentation of coord_equal() for
more details.

Dieter

______________________________________________
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.

Dit bericht en eventuele bijlagen geven enkel de visie van de schrijver weer 
en binden het INBO onder geen enkel beding, zolang dit bericht niet bevestigd is
door een geldig ondertekend document. The views expressed in  this message 
and any annex are purely those of the writer and may not be regarded as stating 
an official position of INBO, as long as the message is not confirmed by a duly 
signed document.