R help - Mar 2010 - Changing axis origin for plot

Hi all,

I am plotting data using the simple plot function:

plot(data$x, data$y)

which results in a standard plot with the axis origin in the lower left corner.

^
|
|
|
|
| O O
| O O
---------------------------------->

Since my data are screen coordinates I need mirrored axis so that the
origin for both axis is in the upper left corner; like this:

|-------------------------------->
| O O
| O O
|
|
|
|
|
v

Anybody know how? I did not find any parameter when consulting the
help file. I assume its a more general parameter but where is that
documented?

Ralf

On 03/24/2010 11:08 AM, Ralf B wrote:
> Hi all,
>
> I am plotting data using the simple plot function:
>
> plot(data$x, data$y)
>
> which results in a standard plot with the axis origin in the lower left
corner.
>
> ^
> |
> |
> |
> |
> | O O
> | O O
> ---------------------------------->
>
> Since my data are screen coordinates I need mirrored axis so that the
> origin for both axis is in the upper left corner; like this:
>
> |-------------------------------->
> | O O
> | O O
> |
> |
> |
> |
> |
> v
>
> Anybody know how? I did not find any parameter when consulting the
> help file. I assume its a more general parameter but where is that
> documented?
Hi Ralf,
I don't know of any options or call to "par" that will change
which axes
are displayed. You can do what you want like this:

plot(...,xaxt="n")
axis(3,...)

unless you want to reverse the direction of the ordinate (y-axis). In 
that case, have a look at the revaxis function in the plotrix package.

Jim