Answered

Runge Kutta Fourth order and Interpolation

Shouldn't f1 = @(z,r,ed,p11,m11) -(ed+p11)*z*m11.^3 *((r+1)./(((ed+p11)*(r.^2 +z.^2).^6) -(r/p11))) ./(2*pi*(r.^2 + z.^2)) ; ...

Runge Kutta Fourth order and Interpolation

Shouldn't f1 = @(z,r,ed,p11,m11) -(ed+p11)*z*m11.^3 *((r+1)./(((ed+p11)*(r.^2 +z.^2).^6) -(r/p11))) ./(2*pi*(r.^2 + z.^2)) ; ...

3 months ago | 0

Answered

Newton Raphson method for a system of non-linear equations?

Here's a simple example for you to follow: % Functions f = @(x,y) x^2 + y - 5.94; % i.e. the equation is x^2+y=5.94 g = @(x,...

Newton Raphson method for a system of non-linear equations?

Here's a simple example for you to follow: % Functions f = @(x,y) x^2 + y - 5.94; % i.e. the equation is x^2+y=5.94 g = @(x,...

4 months ago | 0

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Answered

No feasible solution in optimisation in linprog

I don't know if this will fix your problem, but I think the first number in the second row of A1 should be 8 not 2.

No feasible solution in optimisation in linprog

I don't know if this will fix your problem, but I think the first number in the second row of A1 should be 8 not 2.

4 months ago | 0

Answered

Simple relaxation method Matlab

For the simple relaxation technique to work the A matrix needs to be diagonally dominant. Your A is not diagonally dominant - s...

Simple relaxation method Matlab

For the simple relaxation technique to work the A matrix needs to be diagonally dominant. Your A is not diagonally dominant - s...

4 months ago | 0

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Answered

Solve a system of 3 second order equations

Write your equations as 6 first order equations like so: where I've assumed you have pre-defined omegaout and thetaout as fun...

Solve a system of 3 second order equations

Write your equations as 6 first order equations like so: where I've assumed you have pre-defined omegaout and thetaout as fun...

4 months ago | 0

Answered

Unable to solve nonlinear equation using fsolve as the message shows No solution found

fminsearch makes a reasonable attempt: F1 = @(a,b) -9.135789053E+00-log(a)+166.2509975*a+5.84074229*b+... -166.2509975*a^2...

Unable to solve nonlinear equation using fsolve as the message shows No solution found

fminsearch makes a reasonable attempt: F1 = @(a,b) -9.135789053E+00-log(a)+166.2509975*a+5.84074229*b+... -166.2509975*a^2...

4 months ago | 2

Answered

How to solve and plot this set of differential equations?

If rho starts at 0, then drho/dtheta will be zero and rho will not change from zero according to your first ode. If rho and drh...

How to solve and plot this set of differential equations?

If rho starts at 0, then drho/dtheta will be zero and rho will not change from zero according to your first ode. If rho and drh...

4 months ago | 0

Answered

How can I add two differential equations to the system in a given time interval?

Like this? (though I'm not sure I've interpreted which constants apply during which interval correctly!) Tspan = 0:30; C0 =...

How can I add two differential equations to the system in a given time interval?

Like this? (though I'm not sure I've interpreted which constants apply during which interval correctly!) Tspan = 0:30; C0 =...

4 months ago | 1

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Answered

How do I plot Rosette-like diagram in this case?

Something like this? data=[10 10 30 100; 20 50 70 150; 30 45 60 120]; theta0 = deg2rad(data(:,2)); thetaf = deg2r...

How do I plot Rosette-like diagram in this case?

Something like this? data=[10 10 30 100; 20 50 70 150; 30 45 60 120]; theta0 = deg2rad(data(:,2)); thetaf = deg2r...

4 months ago | 1

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Answered

Iteration of multiple nonlinear functions

Here's a quick and dirty way. I'll leave you to modify the following to record all the temperatures at every step. %Given valu...

Iteration of multiple nonlinear functions

Here's a quick and dirty way. I'll leave you to modify the following to record all the temperatures at every step. %Given valu...

4 months ago | 0

Answered

using num2str for subplot titles

Try title(['Q1S', num2str(k)]) i.e. enclose the two terms within square brackets.

using num2str for subplot titles

Try title(['Q1S', num2str(k)]) i.e. enclose the two terms within square brackets.

4 months ago | 0

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Answered

control and simulation of petroleum distillation column

The following works, but probably doesn't contain all the right data or equations! % CALCULATE MATERIAL BALANCES FOR THE DISTIL...

control and simulation of petroleum distillation column

The following works, but probably doesn't contain all the right data or equations! % CALCULATE MATERIAL BALANCES FOR THE DISTIL...

4 months ago | 0

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Answered

Error with plot command

You haven't specified function atten_func_dist, so we can't run your code to test it. You specify fre as a constant, then us...

Error with plot command

You haven't specified function atten_func_dist, so we can't run your code to test it. You specify fre as a constant, then us...

4 months ago | 2

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Answered

How to combine multiple curve fits in one plot

Use hold on after plotting the first figure

How to combine multiple curve fits in one plot

Use hold on after plotting the first figure

5 months ago | 0

Answered

How to represent [airfoil] coordinates as a polynomial

How about using a spline fit? After loading your data and calling the first column x and the second column y try xfit = linspa...

How to represent [airfoil] coordinates as a polynomial

How about using a spline fit? After loading your data and calling the first column x and the second column y try xfit = linspa...

5 months ago | 0

Answered

1D melting problem with Neumann's analytical solution

eps is a built-in constant so better not to use it as a variable. Your png files show it is xi not epsilon. Try the following ...

1D melting problem with Neumann's analytical solution

eps is a built-in constant so better not to use it as a variable. Your png files show it is xi not epsilon. Try the following ...

5 months ago | 0

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Answered

Overlay plots of different angles of incidence.

Remove the word figure and add hold on after the plot grid on [Fr,In] = meshgrid(Frequency,Incident); plot3(Fr,In,Reflectivit...

Overlay plots of different angles of incidence.

Remove the word figure and add hold on after the plot grid on [Fr,In] = meshgrid(Frequency,Incident); plot3(Fr,In,Reflectivit...

5 months ago | 0

Answered

How can write in MATLAB the following expression?

Try ket0 = [1; 0; 0] ket1 = [0; 1; 0]

How can write in MATLAB the following expression?

Try ket0 = [1; 0; 0] ket1 = [0; 1; 0]

5 months ago | 0

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Answered

I don't understand why does it give error?

Put the functions at the end. Tidy up one or two minor errors to get: %########### BF-PSO.m file ############# %####### Butter...

I don't understand why does it give error?

Put the functions at the end. Tidy up one or two minor errors to get: %########### BF-PSO.m file ############# %####### Butter...

5 months ago | 0

Answered

How to count steps represented by the acceleration data given in text file?

Like this (you can plot the other two - look up help on subplot): M = csvread('walking.txt'); x = M(:,1); y = M(:,2); z = M(:,...

How to count steps represented by the acceleration data given in text file?

Like this (you can plot the other two - look up help on subplot): M = csvread('walking.txt'); x = M(:,1); y = M(:,2); z = M(:,...

5 months ago | 0

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Answered

Bisection method add iteration table into my code

Something like this? my_fun = @(x) exp(x) - 3*x; low = 0; high = 1; tolerance = .00001; [x, x0] = bisection(my_fun, low, hi...

Bisection method add iteration table into my code

Something like this? my_fun = @(x) exp(x) - 3*x; low = 0; high = 1; tolerance = .00001; [x, x0] = bisection(my_fun, low, hi...

5 months ago | 0

Answered

I'm trying to solve this code for internal ballistic using ode45.This is my first time using ode

This works (note that Matlab doesn't accept implied multiplication), but doesn't look sensible - what about deriv(2)? y_initial...

I'm trying to solve this code for internal ballistic using ode45.This is my first time using ode

This works (note that Matlab doesn't accept implied multiplication), but doesn't look sensible - what about deriv(2)? y_initial...

5 months ago | 0

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Answered

Error with brackets symsum

Do you mean something more like this? N = 100; % Total number of particles one = 1; alpha = 1; K = 7; % 7 states n0 = 4*o...

Error with brackets symsum

Do you mean something more like this? N = 100; % Total number of particles one = 1; alpha = 1; K = 7; % 7 states n0 = 4*o...

5 months ago | 0

Answered

How to deal with rounding error in this example?

How about i = 1:20001; A = -2000 + (i-1)*0.2;

How to deal with rounding error in this example?

How about i = 1:20001; A = -2000 + (i-1)*0.2;

6 months ago | 1

Answered

Get back variables out of function inside a for loop

Here's one way J = [2.5 27 56]; WZ = [12.2 23.2 33]; M1 = 22; I1 = 2600; for ii = 1:numel(WZ) slope(ii) = (J(ii)-M1)...

Get back variables out of function inside a for loop

Here's one way J = [2.5 27 56]; WZ = [12.2 23.2 33]; M1 = 22; I1 = 2600; for ii = 1:numel(WZ) slope(ii) = (J(ii)-M1)...

6 months ago | 1

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Answered

Plot dispersion curves using Bloch theorem

Like this? OmegaR = 1; mR = 0.125; Omega = 0:0.01:2.5; mu = acos(1 - Omega.^2.*(1+mR./(1-Omega.^2/OmegaR^2))/2); plot(i...

Plot dispersion curves using Bloch theorem

Like this? OmegaR = 1; mR = 0.125; Omega = 0:0.01:2.5; mu = acos(1 - Omega.^2.*(1+mR./(1-Omega.^2/OmegaR^2))/2); plot(i...

6 months ago | 0

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Answered

how to do sensitivity analysis of three variables using MATLAB

Depends what your measure of sensitivity is. One possibility is to do a Monte-Carlo simulation and use the standard error on th...

how to do sensitivity analysis of three variables using MATLAB

Depends what your measure of sensitivity is. One possibility is to do a Monte-Carlo simulation and use the standard error on th...

6 months ago | 0

| accepted