R help - Jun 2006 - how to rotate a triangle image(ZMAT) ?

Hello R users...

 how to align this Zmat (triangle image)  in X axis?
 I would like that the triangle's base become in the X
axis and
 the triangle's height become in the Y axis 

 Is there some trick for make this?

 Thanks.
 Cleber
 

######################## my test and try
 f <- function(x,y){
 z=1-x-y
 z[ z < (-1e-15) ] <- NA 
 return( -100*x+0*y+100*z )
 }

 x = seq( 1, 0, by = -0.01 )
 y = seq( 1, 0, by = -0.01 )
 zmat =  outer(x,y,f)

 image(zmat,  col=terrain.colors(10))
 contour(zmat, add=T)

[Cleber N.Borges]
> how to align this Zmat (triangle image)  in X axis?  I would like that 
> the triangle's base become in the X axis and the triangle's height 
> become in the Y axis.  Is there some trick for make this?
I'm not fully sure of what is the base and the height of the triangle, 
but if I guess correctly, you may peek at "?image", the last paragraph
of the "Details:" section, and also in the "Examples:"
section, where it
says "Need to transpose and flip matrix horizontally.".  Maybe
you'll
find some explanations or ideas in there.
> f <- function(x, y) {
>   z = 1-x-y
>   z[z < (-1e-15)] <- NA
    return(-100*x+0*y+100*z)
> }
> x = seq(1, 0, by = -0.01)
> y = seq(1, 0, by = -0.01)
> zmat = outer(x, y, f)
> image(zmat, col=terrain.colors(10))
> contour(zmat, add=T)
Another idea is to exchange "x, y" in the "outer" call, and
maybe also
use "rev()" on one of them.

-- 
Fran?ois Pinard   http://pinard.progiciels-bpi.ca

I thank Fran?ois Pinard for your attention

one solution, but
very dirty
very ugly
and ~ 30% of calculations cut loose!

if somebody can give a tip, I thank...

Cleber

############
 f <- function(x,y){
 z=1-x-y
 z[ z < (-1e-15) ] <- NA 
 return( -100*x + 0*y + 100*z )
 }

 x = y = seq( 1, 0, by = -0.01 )
 z =  outer(x,y,f)
 
 t1 = length(x)
 aux = numeric(0)
 im  = numeric(0)
 for( i in seq( 1, t1, by = 2 ) ){
    idx = seq( i*t1, t1**2, by = t1 ) - (0:(t1 - i))
    im = c(im, aux, z[idx], aux )
    aux = c(aux, NA)
 }
 im = matrix(im,nr=t1)

 image(im,  col=terrain.colors(256))
 contour(im, add=T)

Cleber N.Borges wrote:
>  Hello R users...
> 
>  how to align this Zmat (triangle image)  in X axis?
>  I would like that the triangle's base become in the X
> axis and
>  the triangle's height become in the Y axis 
> 
>  Is there some trick for make this?
> 
How about:

image(zmat,col=terrain.colors(10),xlim=c(1,0),ylim=c(1,0))

Jim