Answered

contour plot of stream function for a tornado

More like this? m1=-3000; m2 = 5800;%strength R = 0:0.1:20; THETA = linspace(0,2*pi,numel(R)); [r,theta] = meshgrid(R,THET...

contour plot of stream function for a tornado

More like this? m1=-3000; m2 = 5800;%strength R = 0:0.1:20; THETA = linspace(0,2*pi,numel(R)); [r,theta] = meshgrid(R,THET...

1 jour ago | 0

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Answered

Find the intersection between two curves

Look at the fzero function (doc fzero). Express y1-y2 as a function and use fzero.

Find the intersection between two curves

Look at the fzero function (doc fzero). Express y1-y2 as a function and use fzero.

2 jours ago | 1

Answered

equation system with time and space derivation

You could use the pdepe function (try doc pdepe). Alternatively, explicitly discretise z and use ode45 to solve the time depend...

equation system with time and space derivation

You could use the pdepe function (try doc pdepe). Alternatively, explicitly discretise z and use ode45 to solve the time depend...

2 jours ago | 0

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Answered

how to stop executing while loop?

Use a condition inside the while loop, such as if x>10, break, end

how to stop executing while loop?

Use a condition inside the while loop, such as if x>10, break, end

2 jours ago | 0

Answered

How to solve an ODE with 2 initial conditions and 2 unknown parameters and 3 boundary conditions (overdetermined?)

The following is as close as I can get. You might be able to do better by altering tolerances using setoptions, but I'll leave ...

How to solve an ODE with 2 initial conditions and 2 unknown parameters and 3 boundary conditions (overdetermined?)

The following is as close as I can get. You might be able to do better by altering tolerances using setoptions, but I'll leave ...

2 jours ago | 0

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Answered

Can anybody help me?

Change Pprime(i) = P.*(lambda) to Pprime(i) = P.*(lambda(i));

Can anybody help me?

Change Pprime(i) = P.*(lambda) to Pprime(i) = P.*(lambda(i));

2 jours ago | 0

Answered

Approximating /transforming /absolute error

For display purposes you can use fprintf: >> r=3;h=8;Dv=0.1; Dr=(Dv/3)*(1/(1/3*pi*h*2*r)); fprintf('%0.2g \n',Dr) 0.00066

Approximating /transforming /absolute error

For display purposes you can use fprintf: >> r=3;h=8;Dv=0.1; Dr=(Dv/3)*(1/(1/3*pi*h*2*r)); fprintf('%0.2g \n',Dr) 0.00066

3 jours ago | 1

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Answered

Finding roots using Newton raphson method

Just get rid of the first line, you don't need it f=@(y) exp(y)-(sin(pi*y/3)); df=@(y) exp(y)-((pi*cos(pi*y/3))/3); x(1)=-3...

Finding roots using Newton raphson method

Just get rid of the first line, you don't need it f=@(y) exp(y)-(sin(pi*y/3)); df=@(y) exp(y)-((pi*cos(pi*y/3))/3); x(1)=-3...

3 jours ago | 1

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Answered

How to solve multivariable ODE

If you don't have the symbolic toolbox available you could just do something like the following % Define gradient function wher...

How to solve multivariable ODE

If you don't have the symbolic toolbox available you could just do something like the following % Define gradient function wher...

3 jours ago | 0

Answered

How can I plot this second-order differential equation

More like this perhaps omega = 0.8:0.1:1.5; n = numel(omega); for i = 1:n dydt = @(t,y) [y(2); -0.2*y(2) + y(1) - y(1)...

How can I plot this second-order differential equation

More like this perhaps omega = 0.8:0.1:1.5; n = numel(omega); for i = 1:n dydt = @(t,y) [y(2); -0.2*y(2) + y(1) - y(1)...

3 jours ago | 0

Answered

How can I use a string in legend()?

You could use Legend = ['HS+HG = 0.5+5' ;'HS+HG = 1+5']; legend(Legend) But make sure there are the same number of characte...

How can I use a string in legend()?

You could use Legend = ['HS+HG = 0.5+5' ;'HS+HG = 1+5']; legend(Legend) But make sure there are the same number of characte...

4 jours ago | 0

Answered

Inverse hyperbolic fit to data

Here's an alternative, with V as the independent variable and P as the dependent one: % Data P = [5 7.5 10 12.5 15 17.5 20 25...

Inverse hyperbolic fit to data

Here's an alternative, with V as the independent variable and P as the dependent one: % Data P = [5 7.5 10 12.5 15 17.5 20 25...

4 jours ago | 2

Answered

make a function recursive (koch snowflake)

The following replaces the "for iteration = 1:n" loop with a recursive function %Koch draws Koch snowflake %n is how many iter...

make a function recursive (koch snowflake)

The following replaces the "for iteration = 1:n" loop with a recursive function %Koch draws Koch snowflake %n is how many iter...

4 jours ago | 0

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Answered

What is wrong with my code?

Your code works if you put in sensible numbers for step size and velocity. Zero is not sensible!

What is wrong with my code?

Your code works if you put in sensible numbers for step size and velocity. Zero is not sensible!

5 jours ago | 0

Answered

How can I solve it: Matrix dimensions must agree.

Replace if M ==[] with if isempty(M)

How can I solve it: Matrix dimensions must agree.

Replace if M ==[] with if isempty(M)

5 jours ago | 0

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Answered

Getting a wrong answer using solve()

Running your code as is (I copied and pasted, with no changes), I get >> syms pa p1a; c=1.056; Eq1= -8 * p1a ^ 2 + (12 * c -...

Getting a wrong answer using solve()

Running your code as is (I copied and pasted, with no changes), I get >> syms pa p1a; c=1.056; Eq1= -8 * p1a ^ 2 + (12 * c -...

5 jours ago | 1

Answered

Best fit line on Semi log graph

Like so data=[0.891 35784.525582 0.91 39142.72 0.815 17679.26 0.891 25582 0.8861 30168.052]; ...

Best fit line on Semi log graph

Like so data=[0.891 35784.525582 0.91 39142.72 0.815 17679.26 0.891 25582 0.8861 30168.052]; ...

5 jours ago | 1

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Answered

How to Plot a Fourier Series?

Here's the cosine version. You can add the sin version and play with different ranges for n: x = -24:0.1:24; n = 10; ycos = f...

How to Plot a Fourier Series?

Here's the cosine version. You can add the sin version and play with different ranges for n: x = -24:0.1:24; n = 10; ycos = f...

5 jours ago | 0

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Answered

How to plot an implicit and dicontinues function?

Do you mean like this (type doc contour for more detail): x1 = -2:0.01:2; x2 = -2:0.01:2; [x, y] = meshgrid(x1, x2); z = T...

How to plot an implicit and dicontinues function?

Do you mean like this (type doc contour for more detail): x1 = -2:0.01:2; x2 = -2:0.01:2; [x, y] = meshgrid(x1, x2); z = T...

5 jours ago | 0

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Answered

Multiple roots formula with Matlab

I think your formula shoud be First define your function and its first two derivatives in Matlab f = @(x) x.^4- 6*x.^3 + 12*...

Multiple roots formula with Matlab

I think your formula shoud be First define your function and its first two derivatives in Matlab f = @(x) x.^4- 6*x.^3 + 12*...

5 jours ago | 0

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Answered

How to plot an implicit and dicontinues function?

Something like the following? (You could use surfc if you want contours as well): x1 = -10:10; x2 = -10:10; [x, y] = meshgr...

How to plot an implicit and dicontinues function?

Something like the following? (You could use surfc if you want contours as well): x1 = -10:10; x2 = -10:10; [x, y] = meshgr...

6 jours ago | 0

Answered

plotting the graph, help me~~

You had a few mismatches between vgs and Vgs. Matlab is case sensitive. Try W=40; Vth=0.45; Leff=0.15; k=4.255*(10^-4)*(W/L...

plotting the graph, help me~~

You had a few mismatches between vgs and Vgs. Matlab is case sensitive. Try W=40; Vth=0.45; Leff=0.15; k=4.255*(10^-4)*(W/L...

6 jours ago | 0

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Answered

Recursive Function in Matlab (Help)

The Newton_Raphson is a recurrence formula, not a recursive one, so what you have written is correct. Look at the last value o...

Recursive Function in Matlab (Help)

The Newton_Raphson is a recurrence formula, not a recursive one, so what you have written is correct. Look at the last value o...

6 jours ago | 0

Answered

NUMERICAL INTEGRATION USING SIMPSONS

The problem is that you have many values of lambda. To deal with this use a loop to do the integration for each value of lambda...

NUMERICAL INTEGRATION USING SIMPSONS

The problem is that you have many values of lambda. To deal with this use a loop to do the integration for each value of lambda...

6 jours ago | 0

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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) ....

7 jours ago | 1

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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.

7 jours 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...

7 jours ago | 0

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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...

7 jours 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...

8 jours ago | 0

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