Callback Function for update plot with multiple functions

Hi, I need the slider bar to adjust all three of the functions on the plot, but I don't know how to make a callback to update it. Plot picture is attached and c

ode is here:

% 3.131

k = 180; %W/m K
L = 10e-3; %m
t = 1e-3; %m
Tb = 100 + 273; %K
Tinf = 25 + 273; %K
h = linspace(10,1000,20);

m = sqrt(2 .* h ./ (k * t));
M = sqrt(2 .* h .* t .* k) .* (Tb-Tinf);

qfa = M .* (sinh(m .* L)+(h ./ (m .* k)) .* cosh(m .* L)) ./ (cosh(m .*L) + (h ./ (m .*k)).*sinh(m.*L));

qfb = M .* tanh(m.*L);

qfd = M;

f = figure;

plot(h,qfa,'k','DisplayName','qfa'); hold on;
plot(h,qfb,'b','DisplayName','qfb');
plot(h,qfd,'r','DisplayName','qfd');
xlabel('Convection coefficient, h(W/m^2 * K)'); ylabel('Heat rate,qf(W/m)'); title('Heat rate vs h for different boundary conditions');
legend('show')

b = uicontrol('Parent',f,'Style','slider','Position',[81,54,419,50],...
    'value',k,'min',15,'max',180);
bgcolor = f.Color;
bl1 = uicontrol('Parent',f,'Style','text','Position',[50,54,23,50],...
    'String','15','BackgroundColor',bgcolor);
bl2 = uicontrol('Parent',f,'Style','text','Position',[500,54,23,50],...
    'String','180','BackgroundColor',bgcolor);
bl3 = uicontrol('Parent',f,'Style','text','Position',[240,50,100,40],...
    'String','Conduction Coefficient, k(W/m K)','backgroundColor',bgcolor);

[Walter Roberson]

You have not defined what the slider should do .

[Maxsam Donta]

The slider should change the value of k and should adjust the plot accordingly

Answer 1

[Rik]

If that k should contain the value of the slider, make sure the slider exist before the first plot and the use k=get(b,'Value').

[Maxsam Donta]

Thank you for your response. There are no longer errors when I do this, but the graph doesn't change when I move the slider.

Answer 2

[Jan]

See https://www.mathworks.com/matlabcentral/answers/292993-continuous-slider-callback-not-updated-handles-in-callback-function and https://www.mathworks.com/matlabcentral/answers/264979-continuous-slider-callback-how-to-get-value-from-addlistener for defining a callback, which is triggered during moving the slider, not only when releasing it.

[EDITED] Try this:

function YourGUI
k = 180; %W/m K

FigH = figure;
handles.gfaPlot = plot(h,qfa,'k','DisplayName','qfa');
hold on;
handles.gfbPlot = plot(h,qfb,'b','DisplayName','qfb');
handles.gfdPlot = plot(h,qfd,'r','DisplayName','qfd');

xlabel('Convection coefficient, h(W/m^2 * K)');
ylabel('Heat rate,qf(W/m)');
title('Heat rate vs h for different boundary conditions');
legend('show')

handles.Slider = uicontrol('Parent',f,'Style','slider', ...
          'Position',[81,54,419,50],...
          'value',k,'min',15,'max',180, ...
          'Callback', {@yourSliderCallback, handles});
bgcolor = f.Color;
uicontrol('Parent',f,'Style','text','Position',[50,54,23,50],...
  'String','15','BackgroundColor',bgcolor);
uicontrol('Parent',f,'Style','text','Position',[500,54,23,50],...
  'String','180','BackgroundColor',bgcolor);
uicontrol('Parent',f,'Style','text','Position',[240,50,100,40],...
  'String','Conduction Coefficient, k(W/m K)', ...
          'backgroundColor',bgcolor);
end

function [h, gfa, gfb, gfd] = YourCalculation(k)
L = 10e-3; %m
t = 1e-3; %m
Tb = 100 + 273; %K
Tinf = 25 + 273; %K
h = linspace(10,1000,20);
m = sqrt(2 .* h ./ (k * t));
M = sqrt(2 .* h .* t .* k) .* (Tb-Tinf);
qfa = M .* (sinh(m .* L)+(h ./ (m .* k)) .* cosh(m .* L)) ./ ...
           (cosh(m .*L) + (h ./ (m .*k)).*sinh(m.*L));
qfb = M .* tanh(m.*L);
qfd = M;
end

function yourSliderCallback(SliderH, EventData, handles)
k = get(SliderH, 'Value');
[h, gfa, gfb, gfd] = YourCalculation(k);
set(handles.gfaPlot, 'YData', gfa);
set(handles.gfbPlot, 'YData', gfb);
set(handles.gfdPlot, 'YData', gfd);
end

Now the callback of the slider calculates the new values and updates the Y-positions of the lines. The callback is triggered, when the mouse is released. Using the "continuous slider callback" as explained at first in my message would change the value wile the slider is moved already.

[Maxsam Donta]

Thank you for your response. I am very new to Matlab and programming in general, so I unfortunately I'm lost with these references as for what they mean and what to do.