How to move slider-bar with a step-size of two?

Hey there everyone. I have a slider which I want to increase like 1:2:10 by dragging the bar with mouse. How can I accomplish that?

Thanks in advance!

[Rik]

I don't know if you have already come across this page, but especially since GUIDE is going to be removed from Matlab, here are some useful tips: https://www.mathworks.com/matlabcentral/answers/483657-how-to-create-a-gui

Answer 1

[Rik]

Round the Value property to the nearest value in your array in the callback function.

allowed_vals=1:2:10;%better: store this in the guidata struct
val=3.2;%val=get(hObject,'Value');
[~,idx]=min(abs(allowed_vals-val));
val_rounded=allowed_vals(idx);

%set(hObject,'Value',val_rounded);
disp(val_rounded)

[John Doe]

Hello Rik. Thanks for the neat answer. It works.

[~,idx]=min(abs(allowed_vals-val));
val_rounded=allowed_vals(idx);

Could you please explain these two lines? And also by the guidata struct, did you mean where the callback of slider is written and insert the allowable range in there?

[Rik]

Did you read the documentation for these functions?

[~,idx]=min(abs(allowed_vals-val));
%subtract the value of the slider from the allowed values
%then take the absolute value to calculate the distance between the current value and all allowed values
%use the min funtion to find the index with the lowest difference

val_rounded=allowed_vals(idx);
%use the index of the lowest difference to select the value from the array

And the guidata struct is called handles in a GUIDE GUI. It is the variable that is stored with your GUI figure, so it is a good way to share data between callbacks. You can set a value in the StartupFcn and use that in your callback. That way you have a place that makes sense to set an array of allowed values, and you give yourself the option of having some callback modify this array (e.g. if you implement a data set selector that uses different ranges).

[John Doe]

I see. Thanks for the explanation.

Actually, I am trying to pass this slider value to a filter.

x = imboxfilt(Dummyimage,sliderval)

When I increase the slider, the picture gets blurred. But then when I decrease the value, the blurness does not decrease. I want the blur amount to vary with the slider value.

Is it because the pixels are already averaged and cannot be reverted back? Is there a way to solve this issue? Thanks.

[Rik]

You need to blur the original image, so you will have to store both the original and the processed version.