ODE45 arguments not working

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David Geistlinger
David Geistlinger 2018-11-14
编辑： madhan ravi 2018-11-14
Not sure why this isnt working. I cut and pasted same code from other ODE45 function for 50kg jumper. All i changed was the variable u to v for this one. The other formula works great this one is giving me errors.
Error in odearguments (line 90)
f0 = feval(ode,t0,y0,args{:}); % ODE15I sets args{1} to yp0.
Error in ode45 (line 115)
odearguments(FcnHandlesUsed, solver_name, ode, tspan, y0, options, varargin);
Error in DriverProgram (line 85)
[t2, v]=ode45(@ODE4590kg,[0:0.1:300],[0,0]);
Top code is ODE function and below is script to run it:
function [vprime] = ODE4590kg(t2,v )
% Set known variables
vprime =[0;0];
m = 90;
g = 9.81;
W= m*g;
c= W/55^2;
D= c.*(v(1)).^2;
B= 100*(v(2)-8);
R= 3.*(v(1));
if v(2) >= 0 && v(2) <= 8
vprime(1) = (W-D)/m;
vprime(2) = v(1);
else
vprime(1) = (W-D-B-R)/m;
vprime(2) = v(1);
end
end
%%
[t2, v]=ode45(@ODE4590kg,[0:0.1:300],[0,0]); %Line 85
xx2_prime = v(:,1); % all rows and column 1 of u
xx2 = v(:,2); % all rows and column 2 of u
ma = 90;
gr = 9.81; %Line 90
we= ma*gr;
co= we/55^2;
dr= co.*(xx2_prime).^2;
bu= 100.*(xx2-8);
re= 3.*(xx2_prime);
if xx2 >= 0 & xx2 <= 8
xx2_double_prime = (we-dr)./ma;
else
xx2_double_prime= (we-dr-bu-re)./ma;
end
figure(2)
subplot(3,2,2) % first 2x1 subplot %Line 115
plot(t2,xx2),title('90 kg ODE 45'),xlabel('Time'),ylabel('Position'),axis([0,300,0,30])
subplot(3,2,4) % second 2x1 subplot
plot(t2,xx2_prime),title('90 kg ODE45'),xlabel('Time'),ylabel('Velocity'),axis([0,300,-20,20])
subplot(3,2,6) % first 2x2 subplot
plot(t2,xx2_double_prime),title('90 kg ODE 45'),xlabel('Time'),ylabel('Acceleration'),axis([0,300,-20,10])

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madhan ravi
madhan ravi 2018-11-14
编辑：madhan ravi 2018-11-14
%%
[t2, v]=ode45(@ODE4590kg,[0:0.1:300],[0,0]); %Line 85 %FUNCTION CALLING BEFORE FUNCTION DEFINITION
xx2_prime = v(:,1); % all rows and column 1 of u
xx2 = v(:,2); % all rows and column 2 of u
ma = 90;
gr = 9.81; %Line 90
we= ma*gr;
co= we/55^2;
dr= co.*(xx2_prime).^2;
bu= 100.*(xx2-8);
re= 3.*(xx2_prime);
if xx2 >= 0 & xx2 <= 8
xx2_double_prime = (we-dr)./ma;
else
xx2_double_prime= (we-dr-bu-re)./ma;
end
figure(2)
subplot(3,2,2) % first 2x1 subplot %Line 115
plot(t2,xx2),title('90 kg ODE 45'),xlabel('Time'),ylabel('Position'),axis([0,300,0,30])
subplot(3,2,4) % second 2x1 subplot
plot(t2,xx2_prime),title('90 kg ODE45'),xlabel('Time'),ylabel('Velocity'),axis([0,300,-20,20])
subplot(3,2,6) % first 2x2 subplot
plot(t2,xx2_double_prime),title('90 kg ODE 45'),xlabel('Time'),ylabel('Acceleration'),axis([0,300,-20,10])
function [vprime] = ODE4590kg(t2,v ) %function definition
% Set known variables
vprime =[0;0];
m = 90;
g = 9.81;
W= m*g;
c= W/55^2;
D= c.*(v(1)).^2;
B= 100*(v(2)-8);
R= 3.*(v(1));
if v(2) >= 0 && v(2) <= 8
vprime(1) = (W-D)/m;
vprime(2) = v(1);
else
vprime(1) = (W-D-B-R)/m;
vprime(2) = v(1);
end
end

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