How do I use a slider to scroll through an axis or a color bar?

How do I use a slider to scroll through an axis or a color bar?

I have a long set of data and I want to display a portion of it on an axis at a time. I also want to scroll through the colors in the colorbar so I can focus more precisely on a certain range of colors. Can I do this in MATLAB?

Answer 1

[MathWorks Support Team]

Here is a small example which shows how to scroll through an axis using a silder:

function scrollplotdemo

%%%%%Generate and plot data

x=0:1e-2:2*pi;

y=sin(x);

dx=2;

% dx is the width of the axis 'window'

a=gca;

p=plot(x,y);

%%%%%Set appropriate axis limits and settings

set(gcf,'doublebuffer','on');

% This avoids flickering when updating the axis

set(a,'xlim',[0 dx]);

set(a,'ylim',[min(y) max(y)]);

%%%%%Generate constants for use in uicontrol initialization

pos=get(a,'position');

Newpos=[pos(1) pos(2)-0.1 pos(3) 0.05];

% This will create a slider which is just underneath the axis

% but still leaves room for the axis labels above the slider

xmax=max(x);

S=['set(gca,''xlim'',get(gcbo,''value'')+[0 ' num2str(dx) '])'];

% Setting up callback string to modify XLim of axis (gca)

% based on the position of the slider (gcbo)

%%%%%Creating Uicontrol

h=uicontrol('style','slider',...

      'units','normalized','position',Newpos,...

      'callback',S,'min',0,'max',xmax-dx);

Below is an example which shows how to use a slider uicontrol to scroll through the values of a COLORBAR.

function slide1

h = surf(peaks(20));

CD = get(h,'cdata');

Min = min(CD(:));

Max = max(CD(:));

cb=colorbar;

DeltaC = (Max-Min)/10;

set(cb,'units','normalized','ylim',Min+[0 1]);

Pos=get(cb,'position');

S=['set(findobj(gcf,''tag'',''Colorbar''),''YLim'',get(gcbo,''Value'')+[0 ' num2str(DeltaC) '])'];

uic=uicontrol('style','slider','units','normalized',...

      'position',[Pos(1)+0.11 Pos(2) 0.04 Pos(4)],...

      'min',Min,'max',Max-DeltaC,'value',Min,...

      'callback',S);