Answered

Finding Solution of an equation with hyperbolic functions within an interval

First draw a graph of the function to see roughly where the roots are, then use fzero: f = @(x) 2*cos(403*x).*sinh(403*x) + 2*...

Finding Solution of an equation with hyperbolic functions within an interval

First draw a graph of the function to see roughly where the roots are, then use fzero: f = @(x) 2*cos(403*x).*sinh(403*x) + 2*...

7 jours ago | 0

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Answered

How to plot bifurcation with Delay Differential equations?

How about the following for your loop (it assumed you have defined tau earlier in the file): for j=1:N+1 if t(j)<=tau ...

How to plot bifurcation with Delay Differential equations?

How about the following for your loop (it assumed you have defined tau earlier in the file): for j=1:N+1 if t(j)<=tau ...

7 jours ago | 0

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Answered

How to use Find (or any other function) to create an Array

Here's another possible way r = repmat((1:9)',1,5); max(r.*S_dash)

How to use Find (or any other function) to create an Array

Here's another possible way r = repmat((1:9)',1,5); max(r.*S_dash)

9 jours ago | 1

Answered

Euler's Method and Deflection of Cantilever Beam

Your derivative is incorrect for your specified deflection equation. I think your deflection equation is also not quite right....

Euler's Method and Deflection of Cantilever Beam

Your derivative is incorrect for your specified deflection equation. I think your deflection equation is also not quite right....

9 jours ago | 0

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Answered

Runge Kutta 4 method to solve second order ODE

Your integration loop is mightily scrambled. It should be like this x(1) = x0; y(1) = y0; for i=1:length(t)-1 t(i+1) = i*...

Runge Kutta 4 method to solve second order ODE

Your integration loop is mightily scrambled. It should be like this x(1) = x0; y(1) = y0; for i=1:length(t)-1 t(i+1) = i*...

9 jours ago | 0

Answered

ode45 with matrix 1st order ode

Does this help z = -1; %parameter Needs to be negative or T1 blows up. n = 2; T0 = eye(n,n); xspan = [0 5*pi]; opts = odes...

ode45 with matrix 1st order ode

Does this help z = -1; %parameter Needs to be negative or T1 blows up. n = 2; T0 = eye(n,n); xspan = [0 5*pi]; opts = odes...

9 jours ago | 0

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Answered

How can i solve for the maximum? (a little complex)

Here is a brute force and ignorance method! % Maximise Value = (9/7)*Na + (5/4)*Nb + Nc + Nd % Subject to 7*Na + 4*Nb + 3*Nc ...

How can i solve for the maximum? (a little complex)

Here is a brute force and ignorance method! % Maximise Value = (9/7)*Na + (5/4)*Nb + Nc + Nd % Subject to 7*Na + 4*Nb + 3*Nc ...

10 jours ago | 0

Answered

How to plot this?

How about ux = [1 0 -1 0 1]; uy = [0 1 0 -1 0]; % The order is CRU GPCC UDEL APH anticlockwise starting on positive x axis. ...

How to plot this?

How about ux = [1 0 -1 0 1]; uy = [0 1 0 -1 0]; % The order is CRU GPCC UDEL APH anticlockwise starting on positive x axis. ...

10 jours ago | 1

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Answered

Generate signals from trigonometric

More like this perhaps lambda= 1000; dz = 1; z = 0:dz:lambda; f = @(z) (z<lambda/2) - (z>lambda/2); n= 6; %[2 4 6 8 1...

Generate signals from trigonometric

More like this perhaps lambda= 1000; dz = 1; z = 0:dz:lambda; f = @(z) (z<lambda/2) - (z>lambda/2); n= 6; %[2 4 6 8 1...

10 jours ago | 0

Answered

Runga Kutta Mthod 4

As before, your value for h is too large. Set h = 0.01 and it works!

Runga Kutta Mthod 4

As before, your value for h is too large. Set h = 0.01 and it works!

10 jours ago | 0

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Answered

If statement with multiple conditions

Don't forget the indices: if Tp(Tp_Idx)==4 if 30<=r0(r0_Idx)<75 SSGF(Tp_Idx,r0_idx)=(7.84.*10.^(...

If statement with multiple conditions

Don't forget the indices: if Tp(Tp_Idx)==4 if 30<=r0(r0_Idx)<75 SSGF(Tp_Idx,r0_idx)=(7.84.*10.^(...

11 jours ago | 0

Answered

How to solve simultaneously a system of ODEs containing both initial and boundary value problems

Your first two odes could be solved by ode15s, since they don't depend on y(3), then, having solved them, you could investigate ...

How to solve simultaneously a system of ODEs containing both initial and boundary value problems

Your first two odes could be solved by ode15s, since they don't depend on y(3), then, having solved them, you could investigate ...

11 jours ago | 0

Answered

ode; zero input response; drawing the function in matlab

I think you should interpret (D+1)^2y as D^2y + 2Dy + y; i.e. d^2y/dt^2 + 2dy/dt + y Currently you have it as (dy/dt)^2 +2dy/dt...

ode; zero input response; drawing the function in matlab

I think you should interpret (D+1)^2y as D^2y + 2Dy + y; i.e. d^2y/dt^2 + 2dy/dt + y Currently you have it as (dy/dt)^2 +2dy/dt...

11 jours ago | 0

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Answered

Trying to do central difference method

You should probably use the following to calculate the gradient Grad = (f(1+h) - f(1-h))/(2*h); though a much smaller value fo...

Trying to do central difference method

You should probably use the following to calculate the gradient Grad = (f(1+h) - f(1-h))/(2*h); though a much smaller value fo...

11 jours ago | 0

Answered

Dimension and line Error

It looks like you have some t's in your expression for Vy(i) that should be t(i).

Dimension and line Error

It looks like you have some t's in your expression for Vy(i) that should be t(i).

11 jours ago | 0

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Answered

The function return value 'euler' might be unset. Es posible que el valor de retorno de la función 'euler' no esté establecido.

1 Probaby best to have f = euler(... rather than euler = f(... if you want to call the function euler. 2 You need to return yo...

The function return value 'euler' might be unset. Es posible que el valor de retorno de la función 'euler' no esté establecido.

1 Probaby best to have f = euler(... rather than euler = f(... if you want to call the function euler. 2 You need to return yo...

11 jours ago | 0

Answered

How to use ode45 to plot this code?

You have mixed up doing your own iterations with allowing ode45 to do its iterations! For ode45, just use the following N=1000;...

How to use ode45 to plot this code?

You have mixed up doing your own iterations with allowing ode45 to do its iterations! For ode45, just use the following N=1000;...

11 jours ago | 1

Answered

Iterative method to find flowrate in pipe in series

Why would you assume the friction factor in the second pipe is the same as that in the first? You ony apply the head loss to th...

Iterative method to find flowrate in pipe in series

Why would you assume the friction factor in the second pipe is the same as that in the first? You ony apply the head loss to th...

12 jours ago | 0

Answered

Writing a differential equation for iteration using for loop.

This is known as simple Euler integration. It arises from % dx/dt = (a - x^2 - y^2)*x - omega*y % Let dx/dt be approximat...

Writing a differential equation for iteration using for loop.

This is known as simple Euler integration. It arises from % dx/dt = (a - x^2 - y^2)*x - omega*y % Let dx/dt be approximat...

12 jours ago | 1

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Answered

Solve a system of three coupled first-order differential equations

According to the pdf equations, instead of dxdt(3)=(1/(alpha*a))*(1/x(3)-(1+lambda*sin(2*x(2)))*x(3)); you should have dxd...

Solve a system of three coupled first-order differential equations

According to the pdf equations, instead of dxdt(3)=(1/(alpha*a))*(1/x(3)-(1+lambda*sin(2*x(2)))*x(3)); you should have dxd...

12 jours ago | 1

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Answered

Gaussian distribution in Matlab

Try something like >> M = 1; D = 1; % Set your own values c = @(t,x) M/sqrt(4*pi*D*t)*exp(-x.^2/(4*D*t)); x = -5:0.1:5; t...

Gaussian distribution in Matlab

Try something like >> M = 1; D = 1; % Set your own values c = @(t,x) M/sqrt(4*pi*D*t)*exp(-x.^2/(4*D*t)); x = -5:0.1:5; t...

12 jours ago | 0

Answered

System of differential equation -empty sym

ode1=fiff(v)... should probably be ode1=diff(v)...

System of differential equation -empty sym

ode1=fiff(v)... should probably be ode1=diff(v)...

12 jours ago | 0

Answered

Problem with a function

I don't have your daily log returns vector, so I can't check your result. You are the only person who can decide if the function...

Problem with a function

I don't have your daily log returns vector, so I can't check your result. You are the only person who can decide if the function...

13 jours ago | 0

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Answered

Problem with a function

Try changing n=lenght(x); to n=length(x); (Notice the spelling).

Problem with a function

Try changing n=lenght(x); to n=length(x); (Notice the spelling).

13 jours ago | 0

Answered

rung kutta 4th order

Your integration loop isn't that of a fourth order RK routine. Presumably, -2 is standing in for -infinity here, so you correct...

rung kutta 4th order

Your integration loop isn't that of a fourth order RK routine. Presumably, -2 is standing in for -infinity here, so you correct...

13 jours ago | 0

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Answered

help using ODE45

The equations above are a little different from the ones in your initial code, but I've used them in the coding below m0=0.25 ;...

help using ODE45

The equations above are a little different from the ones in your initial code, but I've used them in the coding below m0=0.25 ;...

13 jours ago | 0

Answered

Plotting multiple points in graph

Here is one way x = 1:10; y = 1:10; [x, y] = meshgrid(x,y); plot(x,y,'k.')

Plotting multiple points in graph

Here is one way x = 1:10; y = 1:10; [x, y] = meshgrid(x,y); plot(x,y,'k.')

13 jours ago | 0

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Answered

Runge Kutta method for coupled oscillator system.

Do you mean like this %initializing x,y,t h=0.1; %step size t=0:h:50; x1 = zeros(1,numel(t)); y1 = x1; x2 = x1; y2 = x1; ...

Runge Kutta method for coupled oscillator system.

Do you mean like this %initializing x,y,t h=0.1; %step size t=0:h:50; x1 = zeros(1,numel(t)); y1 = x1; x2 = x1; y2 = x1; ...

14 jours ago | 0

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Answered

Numerical integration using Simpsons

I just get 11 values for I3, running your code!

Numerical integration using Simpsons

I just get 11 values for I3, running your code!

14 jours ago | 0

| accepted