Can I store a function including multiple variable?

Hi,

Im new to matlab, is it able to store function including multiple variable which still can be used? Something like this

x=linspace(1,10,100);
t=linspace(1,5,50);
f=@(x,t,theta) sin(x+t(a)+theta)
for i=1:10
    state{i}=f(:,:,i);
end

where i expect that (but it is not)

state={sin(x+t(a)+1) sin(x+t(a)+2) sin(x+t(a)+3) ... sin(x+t(a)+10)}

so i can used a for loop on t to make a annimation like this

for a=1:length(t)
    for b=1:length(state)
        plot(x,state{b}(a));
    end
end

Is it possible to do something like above or Im using the wrong function?

[Prudhvi Peddagoni]

can you elaborate more on what you are trying to do?

what is the variable a in the anonymous function?

what should the variable state contain and what should be it's length?

[chia ching lin]

I'm trying to make a wave propagating and will change it's phase at the source by time, also consider the retarded potential. The equation suppose to be

E=E0*exp(w(t-x/c)+theta)*u(t-x/c);

where the E0 = amplitude, w = angular frequency, t = time, x = propagate direction, c = 3*10^8, theta = phase, u = step function.

The problem is that if I change the phase at the souce, the whole wave will change. If it only change phase at source, the wave wouldn't look like a a sine or cosine wave when time ends.

The length of state is how much times the phase change. I set the phase change with the time ,so if the time length is 50, the length of the state will be 50. It need to be a variable.

The a is the length of the time , I want all the function in state can run in one for loop changing by time.

[chia ching lin]

https://www.mathworks.com/matlabcentral/answers/617913-propagating-wave-created-by-point-source-adding-random-phase-considering-retarded-potential?s_tid=srchtitle

This is what im trying to do.

Answer 1

[Steven Lord]

You can't call a function handle using :. If you want the anonymous function to "remember" and use the values of x and t that you've defined in the workspace, you can do that.

x = 1:10;
y = 2;
f = @(theta) y*sin(x+theta);
z1 = f(7)
% check
z2 = 2*sin(8:17)

[chia ching lin]

Tks for answering, but this isn't quite I want. I know its able to used multiple variable in function handle, but it is only 'one' function for me to used. Is it able to have the same result as below?

%example
f=sin(x*t+theta);   % function I used
x=[1 2 3 4 5 6 7 8 9 10];   % spactial distribution  % will remain unchange in for loop
t=[1 2 3 4 5];     % time
theta=[1 2 3 4 5];     % phase change by time (will be same length as time)

first, I would like to do something to this function to made it :

F=[ sin(x*t+1) sin(x*t+2) sin(x*t+3) sin(x*t+4) sin(x*t+5)];

so I can call the function for example: F{1}=sin(x*t+1)

next, the function in F need to move together by time :

for b=1:length(theta)     % F{1},F{2},F{3},F{4},F{5}
    for a=1:length(t)    % time change
        A=F{b}(a);      % (a) is suppose to be the time change, but I don't know how to do with it
    end
end

The wave function will times a step function in my code at last, so I cant change the order of my code, it need to be step by step like that.

The length of t and theta will be greater then 1000, so I can't type the function one by one.

Answer 2

[Walter Roberson]

for i=1:10
  state{i}=@(x,t)f(x,t,i);
end

Note that this will be a cell array of function handles and if you wanted an array of results you would need to cellfun

cellfun(@(F) F(x, y), state)

[chia ching lin]

What is the y in the cellfun? And what is F stands for in the code?

How can I fix my code? This is what I get now. I'm not quite sure the usage of the cellfun, need more help.

x=linspace(0,10,100);
t=linspace(0,5,50);
phase=0:pi/3:2*pi;
for i=1:5
    state{i}=@(x,t) sin(x.*t+phase(i));
end
C=cellfun(@(F) F(x,t),state);

Thanks.

[Walter Roberson]

cellfun(@(F) F(x, t), state)