Answered

non linear implicit equation

Surprisingly, this has an explicit solution for y (I didn't use Matlab to get it as I don't have the symbolic toolbox to hand) ....

non linear implicit equation

Surprisingly, this has an explicit solution for y (I didn't use Matlab to get it as I don't have the symbolic toolbox to hand) ....

9 hours ago | 0

Answered

How to write the codes for this gamma function?

Compare your coded value of 154056.7 with the equation's value of 154.056.

How to write the codes for this gamma function?

Compare your coded value of 154056.7 with the equation's value of 154.056.

11 hours ago | 0

Answered

Poisson Boltzmann eq. with an infinite boundary condition

I suspect the initial gradient required to get zero at infinity is an irrational number (or possibly a rational number with a la...

Poisson Boltzmann eq. with an infinite boundary condition

I suspect the initial gradient required to get zero at infinity is an irrational number (or possibly a rational number with a la...

11 hours ago | 0

Answered

How to solve s system of coupled nonlinear ODES already given the state vector

You need to solve for all xdots simultaneously - this is done in matrix format below. There were also a number of errors in you...

How to solve s system of coupled nonlinear ODES already given the state vector

You need to solve for all xdots simultaneously - this is done in matrix format below. There were also a number of errors in you...

15 hours ago | 1

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Answered

Generate and Plot N Points Picking Random Points on Triangle

More like the following; rng('shuffle'); n = 1000; % Set number of points as desired % Let (0,0) be vertex 1, (0,2) be verte...

Generate and Plot N Points Picking Random Points on Triangle

More like the following; rng('shuffle'); n = 1000; % Set number of points as desired % Let (0,0) be vertex 1, (0,2) be verte...

1 day ago | 0

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Answered

Finding the streamlines of a complex potential for a Joukowsky transform from a unit circle to a flat plate.

x=0:. There was a strange vertical line that O thought was related to this. However, you could put it back and see if it makes a...

Finding the streamlines of a complex potential for a Joukowsky transform from a unit circle to a flat plate.

x=0:. There was a strange vertical line that O thought was related to this. However, you could put it back and see if it makes a...

1 day ago | 1

Answered

Finding the streamlines of a complex potential for a Joukowsky transform from a unit circle to a flat plate.

There are some typos in the paper by Smith et al, and some steps left out. I think the following generates figure 18: x = [-2:...

Finding the streamlines of a complex potential for a Joukowsky transform from a unit circle to a flat plate.

There are some typos in the paper by Smith et al, and some steps left out. I think the following generates figure 18: x = [-2:...

1 day ago | 1

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Answered

How to do write the codes for this summation problem?

Having defined n and T then B = 1./(log(T) - mean(log(T))); Note that in Matlab, log is log to base e.

How to do write the codes for this summation problem?

Having defined n and T then B = 1./(log(T) - mean(log(T))); Note that in Matlab, log is log to base e.

1 day ago | 0

Answered

how to graph this system of questions into mathlab

You can define the function as follows f = @(v) (-0.001778*v.^2+0.05333*v).*(v<30); The (v<30) part simply multiplies the rest...

how to graph this system of questions into mathlab

You can define the function as follows f = @(v) (-0.001778*v.^2+0.05333*v).*(v<30); The (v<30) part simply multiplies the rest...

1 day ago | 0

Answered

Initialize values at time = 0

You probably want to replace if (lambda(:,1) == lambda(1,1)) & (lambda(:,2) == lambda(1,2)) by if (lambda(r,1) == lambda(1,1)...

Initialize values at time = 0

You probably want to replace if (lambda(:,1) == lambda(1,1)) & (lambda(:,2) == lambda(1,2)) by if (lambda(r,1) == lambda(1,1)...

1 day ago | 0

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Answered

ode arguments error in function

For the last line in your function you need dYfuncvecdW = [dXdW; dydW]; Notice the semicolon after dXdW Also your plot comman...

ode arguments error in function

For the last line in your function you need dYfuncvecdW = [dXdW; dydW]; Notice the semicolon after dXdW Also your plot comman...

2 days ago | 0

Answered

How do I solve Time dependent parameter in ODE

Perhaps your code needs to be structured more along the following lines; tspan = ..... y0 = ..... options = ..... [t, ymod...

How do I solve Time dependent parameter in ODE

Perhaps your code needs to be structured more along the following lines; tspan = ..... y0 = ..... options = ..... [t, ymod...

3 days ago | 0

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Answered

How to plot min and max values on graph

If you meant you want to highight all the peaks and troughs then the following will do it (assuming you haven't got the findpeak...

How to plot min and max values on graph

If you meant you want to highight all the peaks and troughs then the following will do it (assuming you haven't got the findpeak...

3 days ago | 0

Answered

Plotting a rankine half body

Try this m=3; %strength U = 20;%positive x-axis %Mesh for fourth quadrant and corresponding stream value function [X1,Y1] = ...

Plotting a rankine half body

Try this m=3; %strength U = 20;%positive x-axis %Mesh for fourth quadrant and corresponding stream value function [X1,Y1] = ...

4 days ago | 1

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Answered

Integration by numerical methods

Something like this: z = 0.01:0.01:1; I = zeros(1,numel(z)); for i = 1:numel(z) I(i) = integral(@(x) sqrt(x)./(exp(x)./z(i) ...

Integration by numerical methods

Something like this: z = 0.01:0.01:1; I = zeros(1,numel(z)); for i = 1:numel(z) I(i) = integral(@(x) sqrt(x)./(exp(x)./z(i) ...

4 days ago | 0

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Answered

Can someone help me write out this equation for chi-square please

As long as y, m and err_y have the same number of elements then your expression should work ok.

Can someone help me write out this equation for chi-square please

As long as y, m and err_y have the same number of elements then your expression should work ok.

5 days ago | 0

Answered

How to solve two coupled differential equations using ode45.

The following should help: % tspan = [0 tend]; % IC = [1 0 0]; % initial conditions % [t, X] = ode45(@fn, tspan, IC);...

How to solve two coupled differential equations using ode45.

The following should help: % tspan = [0 tend]; % IC = [1 0 0]; % initial conditions % [t, X] = ode45(@fn, tspan, IC);...

5 days ago | 0

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Answered

Index in position 2 exceeds array bounds (must not exceed 14).

Odd! It works for me: >> C(1,1)= 1; C(1,10) =-1; C(1,16) = 1; C(2,2) = 1; C(2,10) = 1; C(2,11) =-1; C(3,3) = 1; C(3,11) = 1;...

Index in position 2 exceeds array bounds (must not exceed 14).

Odd! It works for me: >> C(1,1)= 1; C(1,10) =-1; C(1,16) = 1; C(2,2) = 1; C(2,10) = 1; C(2,11) =-1; C(3,3) = 1; C(3,11) = 1;...

6 days ago | 0

Answered

how to find a root of polynomial using matlab

Or directly y = sqrt(2)*atan(-1/3);

how to find a root of polynomial using matlab

Or directly y = sqrt(2)*atan(-1/3);

6 days ago | 0

Answered

How to give input function dz/dt=Z*omega*cos(omega) to state space system?

Do you mean something along these lines: tspan = [0 2]; % Or whatever you need IC = [1 0]; % Set your own initial conditi...

How to give input function dz/dt=Z*omega*cos(omega) to state space system?

Do you mean something along these lines: tspan = [0 2]; % Or whatever you need IC = [1 0]; % Set your own initial conditi...

6 days ago | 0

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Answered

how can i solve nonliner equation?

look at documentation on the "roots" function, (ie type help roots).

how can i solve nonliner equation?

look at documentation on the "roots" function, (ie type help roots).

6 days ago | 0

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Answered

How do I solve this bvp4c error ?

You have a division by sinh(k) .../(2*sinh(k)))... Since k is zero, sinh(k) is zero and the resuting expression for vel is NaN...

How do I solve this bvp4c error ?

You have a division by sinh(k) .../(2*sinh(k)))... Since k is zero, sinh(k) is zero and the resuting expression for vel is NaN...

7 days ago | 0

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Answered

Simulate a 2-input linear system with with ode45

More like this: tspan = [0 50]; x0 = [0; 0; 0]; u = [10; 10]; [t,x] = ode45(@(t,x) odefun(t,x,u),tspan,x0); x = x'; My = [...

Simulate a 2-input linear system with with ode45

More like this: tspan = [0 50]; x0 = [0; 0; 0]; u = [10; 10]; [t,x] = ode45(@(t,x) odefun(t,x,u),tspan,x0); x = x'; My = [...

7 days ago | 0

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Answered

Adding Labels to PDE Graph

One way is to do the following with your plot command: plot(x,sol); lg1 = ['t = ',num2str(t(1))]; lg2 = ['t = ',num2str(t(2)...

Adding Labels to PDE Graph

One way is to do the following with your plot command: plot(x,sol); lg1 = ['t = ',num2str(t(1))]; lg2 = ['t = ',num2str(t(2)...

7 days ago | 0

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Answered

How can I get values for n=500, 1000 and 2000 ? only getting values for n=4000!

Your assignments T.Euler_1(p) = abs(init_cond(1) - z(end,1)); etc. are all outside of the for p = ... loop, hence they just re...

How can I get values for n=500, 1000 and 2000 ? only getting values for n=4000!

Your assignments T.Euler_1(p) = abs(init_cond(1) - z(end,1)); etc. are all outside of the for p = ... loop, hence they just re...

7 days ago | 1

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Answered

why this error ??

You have defined x as a 1x25 vector, but you are calling it with two arguments. You need to call it with x(n), rather than x(1,n...

why this error ??

You have defined x as a 1x25 vector, but you are calling it with two arguments. You need to call it with x(n), rather than x(1,n...

7 days ago | 0

Answered

How to find x-values when y-function equals a set value?

With your particular function you can get both values of x immediately from x = b1 + c1*sqrt(log(a1/0.7))*[1, -1];

How to find x-values when y-function equals a set value?

With your particular function you can get both values of x immediately from x = b1 + c1*sqrt(log(a1/0.7))*[1, -1];

7 days ago | 0