error using ode23

function dydt = parasi12(t1,y1)

a=7.2*10^-6;

Gm=2.5*10^-2;

Sp=2.75*10^-5;

yon=6*10^-2;

b=4.7;

son=4.5*10^-1;

B=10^-4;

vm=0.1:0.001:0.2;

gp=sinh(vm);

A=10^-10;

soff=1.3*10^-2;

beta=500;

e1=52;

e2=55;

s=10*10;

D=20;

yoff=1.3*10^-2;

f=50;

v1=sawtooth(2*pi*f*t1);

% v=v+1;

i1=v1.*(y1*Gm+(1-y1)*a.*exp(b*sqrt(gp)));

p1=i1.*v1;

dydt = B*sinh(v1/son).*exp(-y1.^2/yon^2).*exp(p1/Sp).*heaviside(v1)+...

A*sinh(v1/soff).*exp(-yoff^2./(y1.^2)).*exp(1/(1+(beta*p1))).*heaviside(-v1);

vm=0.1:0.001:0.2;

t1=0.01:0.0009:0.1;

[t1,y1] = ode23(@parasi12,t1,0.01)

e1=52;

e2=55;

s=10*10;

D=20;

a=7.2*10^-6;

Gm=2.5*10^-2;

b=4.7;

sp=2.75*10^-5;

yon=6*10^-2;

son=4.5*10^-1;

B=10^-4;

A=10^-10;

soff=1.3*10^-2;

beta=500;

yoff=1.3*10^-2;

gp=tanh(vm);

f=50;

v1=sawtooth(2*pi*f*t1);

plot(t1,y1)

in command window error is coming like

Error using /

Matrix dimensions must agree.

Error in parasi12 (line 25)

A*sinh(v1/soff).*exp(-yoff^2./(y1.^2)).*exp(1/(1+(beta*p1))).*heaviside(-v1);

Error in odearguments (line 90)

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

Error in ode23 (line 114)

odearguments(FcnHandlesUsed, solver_name, ode, tspan, y0, options, varargin);

Error in Untitled3 (line 3)

[t1,y1] = ode23(@parasi12,t1,0.01)

>>

[nune pratyusha]

i want y values but replace of / with ./ is not working.

[Jan]

As said already: The readers have no chance to know, if your code matchs the mathematical formula. So we cannot debug the code with onbly knowing that there is a bug anywhere.

Use the debugger to step through your code line by line to examine, what's going on.

Answer 1

[Jan]

 dydt = B * sinh(v1 / son) .* exp(-y1.^2 ./ yon^2) ...
        .* exp(p1 ./ Sp) .* heaviside(v1) + ...
        A * sinh(v1 / soff) .* exp(-yoff^2 ./ (y1.^2)) ...
        .* exp(1 ./ (1 + (beta * p1))) .* heaviside(-v1); 

I've replaced all / by ./ for an elementwise division. But without seeing the formula, which you want to calculate, this is pure guessing only. In general it is impossible to fix code only by seeing the failing code. The comments are missing.

By the way, 4.5*10^-1 is a multiplication and an expensive power operation, while 4.5e-1 is a cheap constant. Therefore this simpler notation is not only easier to read, but faster also.