How to use two sliders logarithmically spaced to update the plot on the same figure as the sliders are moved?

Hello all, I am facing quite a problem with the usage of sliders. I have created a function which takes two inputs a and b, and accordingly, returns x and y. I plot x and y on a log-log axis to see how the output behaves.

Now I want to create two sliders for a and b spaced logarithmically, so by moving both of the sliders, I can see how the plot changes. I want to update my current figure with the change in a and b through the sliders.

I am at my wit's end on how to solve this problem and I would greatly acknowledge help from the people here.

Thanks, Subharthi

[Jan]

You forgot to ask a question or post useful details. You can easily create two sliders and use the logarithm of their values. If you do not want to create new figures, simply do not create new figures but update the existing diagrams.

For a more specific answer, we need to know and specific details. Posting the current code and showing, what you have tried so far will help. Then ask specific question and you will get useful suggestions in return.

[subharthi chowdhuri]

Hi Jan,

Thanks for the comment. Let me be more specific about this.

1. I have a function [x y]=spectral_graph(a,b). As I change a and b, I get different values of x and y. For a single set of a and b, I plot the output x and y on a log-log graph as using the command, loglog(x,y,.....).

Now on this same graph, I want to see how this plot varies as a and b are changed progressively. The change in a and b has to be logarithmic since I would like to cover at least three decades.

2. The examples what I have seen in the previous Matlab forums, those deal with single slider values and those values are spaced on a linear scale. I am not aware of any post where two sliders are used to update the plots and also where the sliders are spaced in a logarithmic way.

I would like to know how I can create two sliders whose values are spaced logarithmically between [1 10^3] and then how to link those two sliders with a and b, so my plot updates as the sliders are moved along?

Thanks again for the kind help.

Subharthi

[Jan]

The slider works with a linear range and steps only, but it is trivial to calculate the exponentional (not logarithm):

uicontrol('Style', 'Slider', 'Min', 0, 'Max', 3, ...
          'SliderStep', [0.1, 0.1], ...
          'Callback', @SliderCallbackA);
...

function SliderCallbackA(SliderH, EventData)
Value = get(SliderH);
a     = 10 ^ Value;
disp(a)

... now do with a what you want:
updateDiagram('a', a);
% And in the other slider callback:
% updateDiagram('b', a);
end

Creating two sliders works exactly as creating one slider, only do it twice. Perhaps you want to share the values of a and b in the handles struct. Search for "share variables between callbacks" in the forum.

You did not provide any code yet, therefore my "updateDiagram" is a bold guess only. Again: Please post, what you have tried so far, such that suggesting the further steps does not require to guess the complete code.

[subharthi chowdhuri]

Hi Jan,

Thanks a lot for your help. I have been able to solve this problem.

Subharthi