error using ode45 in gui

while debugging code for flat-fire using ode45 it gives error

err0r:-

??? Error while evaluating uicontrol Callback

??? Error using ==> feval
Undefined function or method 'fnflatfiredragwind' for input
arguments of type 'double'.

Error in ==> guitry>togglebutton1_Callback at 187

[t,c,te,ze,ie] =
ode45('fnflatfiredragwind',tspan,c0,options,w1,w2,w3,k);

??? Error while evaluating uicontrol Callback

*

here is the function defined in toggle button

function togglebutton1_Callback(hObject, eventdata, handles)

v0 = str2num(get(handles.edit1,'string'));

theta = str2num(get(handles.edit2,'string'));
theta = theta*pi/180;
w1 = str2num(get(handles.edit3,'string'));

w2 = str2num(get(handles.edit4,'string'));

w3 = str2num(get(handles.edit5,'string'));

k = str2num(get(handles.edit6,'string'));

set(handles.text1,'string',result);
c0 = [0;v0*cos(theta);0;v0*sin(theta);0;0];

options = odeset('events','on');
tspan = [0 10];

[t,c,te,ze,ie] = ode45('fnflatfiredragwind',tspan,c0,options,w1,w2,w3,k);

what is this error ????????????????

please help me for this

thanks

pawan kumar

[Jan]

Please use proper code formatting to improve the readability. Follow the "Markup help" link to learn the details.

Answer 1

[Grzegorz Knor]

Replace line:

[t,c,te,ze,ie] = ode45('fnflatfiredragwind',tspan,c0,options,w1,w2,w3,k);

with:

[t,c,te,ze,ie] = ode45(@fnflatfiredragwind,tspan,c0,options,w1,w2,w3,k);

[Jan]

Why? ODE45 can handle functions as names, as long as they are found in the path. But I would prefer a function handle also.

[Grzegorz Knor]

Compare these examples:

function test

options = odeset('RelTol',1e-4,'AbsTol',[1e-4 1e-4 1e-5]);

ode45(@rigid,[0 12],[0 1 1],options)

function dy = rigid(t,y)

dy = zeros(3,1); % a column vector

dy(1) = y(2) * y(3);

dy(2) = -y(1) * y(3);

dy(3) = -0.51 * y(1) * y(2);

And

function test

options = odeset('RelTol',1e-4,'AbsTol',[1e-4 1e-4 1e-5]);

ode45('rigid',[0 12],[0 1 1],options)

function dy = rigid(t,y)

dy = zeros(3,1); % a column vector

dy(1) = y(2) * y(3);

dy(2) = -y(1) * y(3);

dy(3) = -0.51 * y(1) * y(2);

[Walter Roberson]

When you pass a name as a function, the name will be evaluated in the base workspace to find the function. If the function is local to the file you invoked ode45 from, then it will not be known in the base workspace. Using function handles rather than function names solves this problem.

[pawan kumar]

i used @fnflatfiredragwind in place of fnflatfiredragwind but now the error is different. now it is not accepting the variable which i am passing through ode45 argument to the function file.

this problem comes only when i am using push-button to run the code. in simple(not from gui).it gives no error.

error :-

??? Input argument "k" is undefined.

Error in ==> guitry>fnflatfiredragwind at 180

value = [c(2); -k*(c(2)-w1)^2; c(4); (-k*(c(2)-w1)*(c(4)-w2))-g;

c(6); -k*(c(2)-w1)*(c(6)-w3)];

Error in ==> odearguments at 109

f0 = feval(ode,t0,y0,args{:}); % ODE15I sets args{1} to yp0.

Error in ==> ode45 at 173

[neq, tspan, ntspan, next, t0, tfinal, tdir, y0, f0, odeArgs,

odeFcn, ...

Error in ==> guitry>togglebutton1_Callback at 210

[t,c,te,ze,ie] =

ode45(@fnflatfiredragwind,tspan,c0,options,w1,w2,w3,k);

function file is

function [value,isterminal,dircn] = fnflatfiredragwind(t,c,flag,w1,w2,w3)

g = 9.8;

% c(1) = x; c(2) = dx/dt = vx ; c(3) = y ; c(4) = dy/dt = vy ; c(5) = w

% c(6) = dc/dt = vz

if nargin<7 || isempty(flag)

value = [c(2); -k*(c(2)-w1)^2; c(4); (-k*(c(2)-w1)*(c(4)-w2))-g; c(6); -k*(c(2)-w1)*(c(6)-w3)];

else

switch flag

case 'events'

value = c(3);

isterminal = 1;

dircn = 0;

otherwise

error('function not programmed for this event');

end

end

[Grzegorz Knor]

You don't pass the k argument to the function. Please correct this line:

function [value,isterminal,dircn] = fnflatfiredragwind(t,c,flag,w1,w2,w3,k)

Answer 2

[Jan]

The error means, that the file "fnflatfiredragwind.m" cannot be found in the Matlab path and the current directory (see cd). Where is it? Is it a local subfunction? Then Grzegorz's idea of using a function handle might help.

Answer 3

[Walter Roberson]

Convert

[t,c,te,ze,ie] =
ode45(@fnflatfiredragwind,tspan,c0,options,w1,w2,w3,k);

to

[t,c,te,ze,ie] =
ode45(@(t) fnflatfiredragwind(t,w1,w2,w3,k),tspan,c0,options);

convert

function [value,isterminal,dircn] = fnflatfiredragwind(t,c,flag,w1,w2,w3)

to

function [value,isterminal,dircn] = fnflatfiredragwind(t,c,flag,w1,w2,w3,k)

[pawan kumar]

now the error is

??? Error using ==> guitry>@(t)fnflatfiredragwind(t,w1,w2,w3,k)

Too many input arguments.

Error in ==> odearguments at 109

f0 = feval(ode,t0,y0,args{:}); % ODE15I sets args{1} to yp0.

Error in ==> ode45 at 173

[neq, tspan, ntspan, next, t0, tfinal, tdir, y0, f0, odeArgs, odeFcn, ...

Error in ==> rr>togglebutton1_Callback at 257

[t,c,te,ze,ie] = ode45(@(t) fnflatfiredragwind(w1,w2,w3,k),tspan,c0,options);

Error in ==> gui_mainfcn at 96

feval(varargin{:});

Error in ==> rr at 42

gui_mainfcn(gui_State, varargin{:});

Error in ==> @(hObject,eventdata)rr('togglebutton1_Callback',hObject,eventdata,guidata(hObject))

??? Error while evaluating uicontrol Callback

please reply me a efficient method so that i can make gui of my programme

[Walter Roberson]

Correction:

[t,c,te,ze,ie] =

ode45(@(t) fnflatfiredragwind(t,w1,w2,w3,k),tspan,c0,options);

should be

[t,c,te,ze,ie] =

ode45(@(t,c) fnflatfiredragwind(t,c,[],w1,w2,w3,k),tspan,c0,options);

Answer 4

[pawan kumar]

i tried the above method but still it was giving error but now i got the mistake actually the programme is running using the same code [t,c,te,ze,ie] = ode45('fnflatfiredragwind',tspan,c0,options,w1,w2,w3,k);

but previously the mistake which i was doing is i was displaying sth between button function and variable

function togglebutton1_Callback(hObject, eventdata, handles)

clc

clear all

close all

disp(' ')

v0 = str2num(get(handles.edit1,'string'));

when i remove that the programme executed without error

function togglebutton1_Callback(hObject, eventdata, handles)

thanks

v0 = str2num(get(handles.edit1,'string'));

[Walter Roberson]

Any program that has "clear all" in it is 99%+ likely to be broken.

[Walter Roberson]

Please point me to a reference page or user guide page that shows passing additional variables by placing them after the "options" structure in an ode*() call. I have been unable to find such a page myself; all I have been able to find so far is pages that say specifically that YOU CANNOT DO THAT.