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Alan Stevens


Last seen: Today Active since 2020

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Answered
How to solve two coupled differential equations using ode45.
"Why is my previous code is not working properly by treating the problem to be a DAE." I don't know! "Also I noticed you wrote...

2 días ago | 1

Answered
Multiple Anonym Function return wrong values
Here's one solution: C = [4622 5480 18923]*1e-12; U = [454e3 454e3-20e3 20e3].*sqrt(2); W = Energy(C,U); disp(W) function W...

2 días ago | 0

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Answered
Hi, is it possible to have variables in an ode45 that varies according to another function?
Put something like [T, p, rho, speedsound] = atmos(height); immediately after height = x(1); in function dynameqn. Not sur...

10 días ago | 0

Answered
root finding and plot of graph
Are you looking for something like this? hi = 1e-6; lo = 1e-9; n = 500; dt = (hi-lo)/n; t3 = lo:dt:hi; y = f(t3); subplo...

10 días ago | 0

Answered
Calculator result and MATLAB result are different
Have you checked that both are using degrees, or both radians? The Matlab as you've written it is using radians (use sind(24) a...

13 días ago | 1

Answered
How can I rotate a set of points by an angle around its origin?
Do you mean like this? ITM = [461400.0758 617474.3059 461400.8069 617475.4609 461400.8069 617475.4609 461402.3069 617477.633...

15 días ago | 1

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Answered
Unable to perform assignment because the indices on the left side are not compatible with the size of the right side.
Try replacing x(4) = Velocities(3608.9,5249.3); by x(4,:) = Velocities(3608.9,5249.3); Same for x(5).

18 días ago | 0

Answered
Removing zeros from matrix
Like this? A = [1 2 3 4 5 6; 1 2 3 4 5 6; 1 2 3 4 5 0; 1 2 3 4 0 0; 1 2 3 0 0 0]; B = A'; B=B(:); B(B==0)=[]

alrededor de 2 meses ago | 0

Answered
Error in ODE arguments
I suspect you mean like this (notice the way M divides, using the back-slash): % Numerical solution of IVP % M*xddot + C*x...

alrededor de 2 meses ago | 2

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Answered
How to Approximate The Solution for an Initial Value Problem?
Try f = @(t,x) [x(2); sin(1.9*t)-4*x(1)]; [t,x] = ode45(f,[0,150],[1,0]); plot(t,x)

alrededor de 2 meses ago | 1

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Answered
Creating a set range for a function
(x < 3) && (x > 25) An individual element of x can't be both less than 3 and greater than 25 at the same time. If here are ma...

alrededor de 2 meses ago | 0

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Answered
Plotting the tangent line for newton raphson method
Like this? fx = @(x) x.^2 -2; dfdx = @(x) 2*x; n_step = 7 ; % Anzahl der durchzuführenden Schritte für Newtonverfahren...

alrededor de 2 meses ago | 0

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Answered
Fit scatter plot with a curve
More like ths? x = [0.2337;0.296;0.3071;0.4208;0.2055;0.9597;0.8683;0.243;0.3363;0.2793;0.5292;0.2471;0.2282;0.4774;1.0392;0.43...

alrededor de 2 meses ago | 1

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Answered
Generating random numbers with a different probabilities
Assuming there are just two levels of probability, and that the numbers are real, not just integers, you could try: p50 = 0.75;...

alrededor de 2 meses ago | 1

Answered
Hi, what does ; exactly mean?
It means start a new row, e.g. x = [1 2; 3 4]; disp(x)

alrededor de 2 meses ago | 0

Answered
Solve the IVP y′′′=sin(y2)+y′+cos(t), provided with an appropriate set of initial conditions of your choice, and using Matlab's ODE45 function.
Like this? (Note the IC for d^2y/dt^2 must be consistent with the values chosen for y(0) and dy(0)/dt). Change the IC's and tim...

2 meses ago | 0

Answered
Need Help Solving System of ODEs
You haven't included the first term on the right-hand side of your equation for dV/dt, nor for dgamma/dt.

2 meses ago | 1

Answered
spring mass using ode45
Like this x0 = [0; 0]; tspan = [0, 10]; [t, x] = ode45(@func, tspan, x0); subplot(2,1,1) plot(t, x(:, 1)); grid('on...

2 meses ago | 0

Answered
I am getting error in this program. Please suggest the corrections.
Change c = [1 2 2 3 4 5 6 7]; to c = [1 2 3 4 5 6 7];

2 meses ago | 1

Answered
Hello, I'm trying to plot one non-piecewise function and two piecewise functions in one graph but I keep getting an error. I don't understand the two error messages below.
You need to put the non-local functions at the end, as in the following. There were several other errors. I don't know if my co...

2 meses ago | 0

Answered
How to Solve equation using Eulers method in Matlab?
Here's part (a) for you - definitely not a straight line!

2 meses ago | 0

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Answered
How to get one output for each input into an equation in MATLAB?
mu = mu_max * (x./(x+Ks)); % Notice it is ./ not just /

2 meses ago | 0

Answered
How to solve 'Index number exceeds number of array elements(1)'
You don't update XSOL, so when ct is 2, XSOL(ct) doesn't exist.

2 meses ago | 0

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Answered
A question about FitzHugh-Nagumo model
Like this? tspan = [0 100]; v0 = 0; w0 = 0; IC = [v0 w0]; A=0.5; B=0.05; Epsilon=0.005; I=@(t)sin(t); %%%%%%%%%%%%%%...

2 meses ago | 0

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Answered
How to find parameters that minimize a difference
Use fminsearch and use the norm of the differences. help fminsearch

2 meses ago | 2

Answered
I want to combine 2 variables in matlab into one variable
If they are imported as, say, c1 and c2, then you can simply write c = [c1; c2]; then delete the c1 and c2 if you don't need t...

3 meses ago | 0

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Answered
How can i call an equation and it's derivative inside a matlab function?
Like this, perhaps: % TC is given in terms of percentage! x0=0; TC=10^-4; error=TC+1; i=0; x(1)=x0; while(error>TC) [f...

3 meses ago | 0

Answered
simple Fixed Point Iteration
Probably more like this (though you don't seem to have used function f anywhere): n = 11; x = zeros(1,numel(n)); ea = zeros(1...

3 meses ago | 0

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Answered
I want Estimate log to the base 10 value using 'x' number such that 10^estimated value is equal to or just exceeding x.
< not <= a = log10_bywhile( 50, 0.1 ) b = log10_bywhile( 100, 1 ) function [out] = log10_bywhile(x, inc) esmt = 0; % if...

3 meses ago | 0

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