Re: Lining up the axes of multiplots/subplots

[Matthias Brennwald]

The following works for me:

-------------------------------------
x1 = [1:0.1:10]; x2 = [3:0.1:15]; y1 = sin(x1); y2 = cos(x2);

xLow = floor(min([x1 x2]));
xHigh = ceil(max([x1 x2]));

subplot(2,1,1);
plot(x1,y1);
axis([xLow xHigh min(y1) max(y1)]);

subplot(2,1,2)
plot(x2,y2);
axis([xLow xHigh min(y2) max(y2)]);
-------------------------------------

However, if the labels on the y axes are not of the same width, gnuplot 
may decide to move the position of the y axes, which will spoil the 
alignment of the two plots. If so, you will have to resort to using 
__gnuplot_raw__ . The following example illustrates this:

-------------------------------------
x1 = [1:0.1:10]; x2 = [3:0.1:15]; y1 = sin(x1); y2 = 100000*cos(x2);

xLow = floor(min([x1 x2]));
xHigh = ceil(max([x1 x2]));

subplot(2,1,1);
plot(x1,y1);
__gnuplot_raw__("set lmargin 10; \n")
axis([xLow xHigh min(y1) max(y1)]);

subplot(2,1,2)
plot(x2,y2);
__gnuplot_raw__("set lmargin 10; \n")
axis([xLow xHigh min(y2) max(y2)]);
-------------------------------------

HTH,
Matthias


On 17.11.2006, at 14:36, address@hidden wrote:

> Message: 7
> Date: Fri, 17 Nov 2006 14:35:05 +0100
> From: Joseph Wakeling <address@hidden>
> Subject: Lining up the axes of multiplots/subplots
> To: address@hidden
> Message-ID: <address@hidden>
> Content-Type: text/plain; charset=UTF-8
>
> Hello,
>
> I'm hoping someone can give me some advice on multiplot(), subplot() 
> and
> related commands.  I've played around with them a bit but not had
> success in achieving what I want.
>
> Here's the aim: two plots, one above the other, sharing the same X
> scale.  The X axes must line up together.
>
> I want to plot several data sets in the first plot, and some different
> ones in the second.
>
> Now, I can do ...
>
> #first
> subplot(2,1,1)
> plot(x1,y1)
> hold on
> plot(x2,y2)
> #etc
> hold off
>
> #then
> subplot(2,1,2)
> plot(a1,b1)
> hold on
> plot(a2,b2)
> #etc
> hold off
>
> ... to get the plots one above the other, but this doesn't do anything
> to align the axes.  What commands do I have to use to achieve this?
>
> Two related issues would be (a) the same, but side-by-side and sharing
> the same Y scale, and (b) overplotted graphs, where e.g. the X scale is
> the same but there are two different Y scales on the left and right Y 
> axes.
>
> Can anyone advise?
>
> Many thanks,
>
>     -- Joe