Answered

2D cylindrical boundriondition problem

It looks like vr = 0.8:hr:0.2; is the cause of the problem. This leads to vr being empty!

2D cylindrical boundriondition problem

It looks like vr = 0.8:hr:0.2; is the cause of the problem. This leads to vr being empty!

8 días ago | 0

Answered

I am trying to modulate the carrier with Gaussian pulse using frequency modulation. I tried to write this code. Can any one help is it correct, if not please can you help me in this regard. Thanks

Don't put a space between dot and ^ or dot and *. Also use figure, not figures. Try the folowing f = 12e12; % carrie...

I am trying to modulate the carrier with Gaussian pulse using frequency modulation. I tried to write this code. Can any one help is it correct, if not please can you help me in this regard. Thanks

Don't put a space between dot and ^ or dot and *. Also use figure, not figures. Try the folowing f = 12e12; % carrie...

9 días ago | 0

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Answered

I tried to solve the code in R2015a but constantly getting errors:The following error occurred converting from sym to double.DOUBLE cannot convert the input expression into a double array. If the input expression contains a symbolic variable, use VPA

How about the following: %material property at the left end steel E0=2.1*10^11; G0=0.8*10^11; rho0=7.85*10^3; %material pro...

I tried to solve the code in R2015a but constantly getting errors:The following error occurred converting from sym to double.DOUBLE cannot convert the input expression into a double array. If the input expression contains a symbolic variable, use VPA

How about the following: %material property at the left end steel E0=2.1*10^11; G0=0.8*10^11; rho0=7.85*10^3; %material pro...

9 días ago | 0

Answered

problem with Euler's explicit methode

Because you have initial values of zero for L0=0;M0=0;Z0=0;N0=0; and they multiply the terms on the right-hand side of your f...

problem with Euler's explicit methode

Because you have initial values of zero for L0=0;M0=0;Z0=0;N0=0; and they multiply the terms on the right-hand side of your f...

11 días ago | 0

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Answered

Matrix dimensions must agree.

This works % n all alpha beta gamma min max d=[1 550 8.1000 0.00028 0 680 2 309 8.1000 0.00056 0 360 3 307 8.1000 0.00...

Matrix dimensions must agree.

This works % n all alpha beta gamma min max d=[1 550 8.1000 0.00028 0 680 2 309 8.1000 0.00056 0 360 3 307 8.1000 0.00...

12 días ago | 0

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Answered

When I attempt to run this code, it doesnt stop running. It will only stop when I pause it. Would appreciate any help as to how to fix this?

Your pressure goes negative just after a catalyst weight of 5 kg. Should it do this? Perhaps your equations should be double-c...

When I attempt to run this code, it doesnt stop running. It will only stop when I pause it. Would appreciate any help as to how to fix this?

Your pressure goes negative just after a catalyst weight of 5 kg. Should it do this? Perhaps your equations should be double-c...

12 días ago | 0

Answered

writing and plotting function with multiple conditions

One possibility: f = @(x) 9/5*x*(0<=x & x<1/2)+9/5*(1-x)*(1/2<=x & x<=1); e.g. f(0.1) ans = 0.1800 >> f(0.75) ...

writing and plotting function with multiple conditions

One possibility: f = @(x) 9/5*x*(0<=x & x<1/2)+9/5*(1-x)*(1/2<=x & x<=1); e.g. f(0.1) ans = 0.1800 >> f(0.75) ...

13 días ago | 0

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Answered

Why is my plot figure blank?

You only calculate a single value of B. Presumably the x and y values should vary with nu somehow, but you don't specify how!

Why is my plot figure blank?

You only calculate a single value of B. Presumably the x and y values should vary with nu somehow, but you don't specify how!

13 días ago | 0

Answered

design of journal bearing

Here's an example for l/d = 1/4. Note that because the S scale is logarithmic, it's best to interpolate logarithmically: S...

design of journal bearing

Here's an example for l/d = 1/4. Note that because the S scale is logarithmic, it's best to interpolate logarithmically: S...

13 días ago | 0

Answered

Unable to perform assignment because the indices on the left side are not compatible with the size of the right side. how do I solve the problem?

Replace x_d(i)=[2*sin(2*t(i));4*cos(3*t(i))]; by x_d(:,i)=[2*sin(2*t(i));4*cos(3*t(i))]; Similarly for the others.

Unable to perform assignment because the indices on the left side are not compatible with the size of the right side. how do I solve the problem?

Replace x_d(i)=[2*sin(2*t(i));4*cos(3*t(i))]; by x_d(:,i)=[2*sin(2*t(i));4*cos(3*t(i))]; Similarly for the others.

13 días ago | 0

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Answered

Multiplying vectors resulting in unfinished answer

Use a./b not a/b for element by element division.

Multiplying vectors resulting in unfinished answer

Use a./b not a/b for element by element division.

14 días ago | 0

Answered

Finding 0 in data for n X 2 array

Here's one way: ix = (M(:,1)+M(:,2))==0; M(ix,:) = [];

Finding 0 in data for n X 2 array

Here's one way: ix = (M(:,1)+M(:,2))==0; M(ix,:) = [];

14 días ago | 1

Answered

solve multipe eq in a loop

Your equations are linear in p (p2 to p9, that is, since p1 is constant for all times), so the following is a simple way to solv...

solve multipe eq in a loop

Your equations are linear in p (p2 to p9, that is, since p1 is constant for all times), so the following is a simple way to solv...

15 días ago | 0

Answered

Evaluating a 2nd order ODE using the Runge-Kutta method

More like this: a = 0; b = 1; %n = input('Enter the number of intervals:'); n = 100; h = (b-a)/n; y = [2; -2]; t = 0:h:...

Evaluating a 2nd order ODE using the Runge-Kutta method

More like this: a = 0; b = 1; %n = input('Enter the number of intervals:'); n = 100; h = (b-a)/n; y = [2; -2]; t = 0:h:...

16 días ago | 0

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Answered

How to solve this equation with matlab

Strange way of entering data! However, one way to find the friction factor is a simple fixed point iteration method, such as e...

How to solve this equation with matlab

Strange way of entering data! However, one way to find the friction factor is a simple fixed point iteration method, such as e...

17 días ago | 0

Answered

please help me with this

Simply insert hold xvals = [0 7.2 7.2]; yvals = [0.36 0.36]; plot(xvals,yvals,'--') after your plot command (though the pea...

please help me with this

Simply insert hold xvals = [0 7.2 7.2]; yvals = [0.36 0.36]; plot(xvals,yvals,'--') after your plot command (though the pea...

18 días ago | 0

Answered

Equation of 3D motion with V, An, R

A little more like this perhaps, since you are given explicit expressions for velocities and accelerations (though note that ax ...

Equation of 3D motion with V, An, R

A little more like this perhaps, since you are given explicit expressions for velocities and accelerations (though note that ax ...

19 días ago | 0

Answered

Need Help Solving a system of 2nd and 1st Order ODEs

I think you should be passing only 5, not 6, parameters to your mysys function, which is better written as function dy = mysys(...

Need Help Solving a system of 2nd and 1st Order ODEs

I think you should be passing only 5, not 6, parameters to your mysys function, which is better written as function dy = mysys(...

20 días ago | 2

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Answered

HOW CAN I CORRECT THIS ?

It works for me exactly as you have written it, with no error messages!

HOW CAN I CORRECT THIS ?

It works for me exactly as you have written it, with no error messages!

24 días ago | 0

Answered

Family of ODE with summation

Your System_ni function doesn't seem to have acces to your K_Br matrix. You need to pass it into System_ni or specify it within ...

Family of ODE with summation

Your System_ni function doesn't seem to have acces to your K_Br matrix. You need to pass it into System_ni or specify it within ...

24 días ago | 0

Answered

HOW TO SOLVE A SYSTEM OF FIRST ORDER ODE WITH ODE45 SOLVER (knowing that it contains if statment and other parameter depending on the solutions of the system)?

Look at the two asterisked lines in your temperature section below if y(2) < T_b %*********************************************...

HOW TO SOLVE A SYSTEM OF FIRST ORDER ODE WITH ODE45 SOLVER (knowing that it contains if statment and other parameter depending on the solutions of the system)?

Look at the two asterisked lines in your temperature section below if y(2) < T_b %*********************************************...

24 días ago | 0

Answered

MATLAB problem using euler's explict method

If you let dx/dt = vx, say, and dy/dt = vy, then the accelerations can be written as dvx/dt = -gamma/m*vx*sqrt(vx^2+vy^2), and d...

MATLAB problem using euler's explict method

If you let dx/dt = vx, say, and dy/dt = vy, then the accelerations can be written as dvx/dt = -gamma/m*vx*sqrt(vx^2+vy^2), and d...

24 días ago | 0

Answered

Simulating a free fall-project with ode45

More like this perhaps: hi = 40000; % Initial height start=[hi 0]; % [Initial height, initial velocity] tspan=[0 100]; ...

Simulating a free fall-project with ode45

More like this perhaps: hi = 40000; % Initial height start=[hi 0]; % [Initial height, initial velocity] tspan=[0 100]; ...

25 días ago | 0

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Answered

How to find the time and partial derivative?

You don't really need the power of MATLAB here; elementary calculus will do:

How to find the time and partial derivative?

You don't really need the power of MATLAB here; elementary calculus will do:

25 días ago | 1

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Answered

ı want to calculate the flow variable by the specified input by user. for example when ı take l/d=1 and S=0.20 on the chart and then ı read by hand its almost 4.10. but when ı calculate with my code it gives different result. can you help me?

Use interp1, but get rid of inf (and possibly use more points!) >> S=[0 0.00474 0.0188 0.0446 0.121 0.264 0.631 1.33 6]; >> Q...

ı want to calculate the flow variable by the specified input by user. for example when ı take l/d=1 and S=0.20 on the chart and then ı read by hand its almost 4.10. but when ı calculate with my code it gives different result. can you help me?

Use interp1, but get rid of inf (and possibly use more points!) >> S=[0 0.00474 0.0188 0.0446 0.121 0.264 0.631 1.33 6]; >> Q...

25 días ago | 1

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Answered

Newton Jacobi Nonlinear System

Replace e(k+1)= max(xerr,yerr,zerr); with e(k+1)= max(max(xerr,yerr),zerr);

Newton Jacobi Nonlinear System

Replace e(k+1)= max(xerr,yerr,zerr); with e(k+1)= max(max(xerr,yerr),zerr);

25 días ago | 0

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Answered

how to plot an inverse function?

How about y = -10:10; x = 10-y.^2; plot(x,y),grid xlabel('x'),ylabel('y')

how to plot an inverse function?

How about y = -10:10; x = 10-y.^2; plot(x,y),grid xlabel('x'),ylabel('y')

25 días ago | 0

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Answered

Numerically Solving non-linear differential equation

I guess you could treat the equation as a quadratic in (dy/dt)^2, solve for that, then take the square root to get an expression...

Numerically Solving non-linear differential equation

I guess you could treat the equation as a quadratic in (dy/dt)^2, solve for that, then take the square root to get an expression...

26 días ago | 0

Answered

How can i write this primitive function ?

You need to make the f's a function of N as well. e.g: F=@(x,N)(x^((N)+1))/((N)+1);% Primitive function then make sure you ca...

How can i write this primitive function ?

You need to make the f's a function of N as well. e.g: F=@(x,N)(x^((N)+1))/((N)+1);% Primitive function then make sure you ca...

27 días ago | 0

Answered

periodic boundary conditions for advection for a<0

For left moving instead of ul(J,n)=ul(J-1,n); %peridic BC for left moving shouldn't you have ul(J,n)=ul(J+1,n); %peridic...

periodic boundary conditions for advection for a<0

For left moving instead of ul(J,n)=ul(J-1,n); %peridic BC for left moving shouldn't you have ul(J,n)=ul(J+1,n); %peridic...

27 días ago | 0