Community Profile # Torsten

Last seen: Today Active since 2013

#### Statistics

• • • • • • • #### Content Feed

View by

I don't know why this code is saying, "Arrays have incompatible sizes for this operation."
Your vector of initial conditions is 6x1 y0 = [Pi; Si; Li; Ii; Ri; Bi]; but you only return a 5x1 vector in PSLIR dydt = [dPd...

1 day ago | 0

| accepted

Use off_diagonal = coefficient * ones(N-1, 1); instead of off_diagonal = coefficient * ones(N-2, 1); See the example "Create...

1 day ago | 0

Apply fmincon nonlinear parameter inequality constraints into SimBiology for parameterization
function [c,ceq] = nonlincon(params) %Nonlinear inequality constraints c(1) = params(1)*params(2) - params(5)*params(7); % For...

1 day ago | 0

Trouble with For Loop
for i = 1:35 dataN_(i) = ecg_data (:,i); mean_HR_subject(i) = ... ... end

1 day ago | 0

| accepted

Solving first order ODE with initial conditions and symbolic function
You solved it in your code. The second solution out of the three MATLAB returned is the "correct" one giving real-valued tempera...

1 day ago | 0

| accepted

It takes too long to run the program and in the end I get an error, could you tell me what the error is?
You can't change the input for x in function "campo_pendulo". So you can delete this part of your code because it doesn't influ...

1 day ago | 0

Can someone help me check if I did this correctly?
Replace syms r a0 by syms r a0 positive to get the limits resolved.

1 day ago | 0

| accepted

Fixed Bed Adsorption Column Using Dimensionless Equations
The usual procedure is to define a grid 0 = X(1) < X(2) < ... < X(n) = 1 approximate the spatial derivative dA/dX in grid poin...

2 days ago | 1

| accepted

Index exceeds the number of array elements. Index must not exceed 4.
Maybe you mean for i = 1:nt1 G1 = [(1-(1/2-beta)*w2.*t1(i).^2)/(1+(beta*w2.*t1(i).^2)),t1(i)/(1+(beta*w2.*t1(i).^2)); ...

2 days ago | 1

| accepted

Empty plot is showing because of my er
What x-y data are given to build the Lagrange Polynomial and in which x-data do you want to interpolate ? I assume that x-y are ...

2 days ago | 0

Any availiable function to find the Taylor series of multi variables function in Matlab?

3 days ago | 0

| accepted

I need help displaying the eigenvalue after each iteration
A = rand(10); ATA = A'*A; x0 = rand(10,1); for iter = 1:10 y = ATA*x0; x = y/norm(y); x0 = x; y end lar...

3 days ago | 0

Solving 4 nonlinear equation for 4 unknowns numerical - doesn't find an answer [0×1 sym]
Try S = vpasolve(E,[x1,x2,y1,y2],[0.086 -0.176 1.0125 1.0099]) But the solution is complex-valued since your function h is com...

4 days ago | 0

symbolic solving system of non-linear equations
A system of 12 equations in 6 unknowns usually has no solution since it is overdetermined. Or can you extract 6 of the 12 equati...

4 days ago | 1

how to code a sum of function in matlab
Generate the elements that you want to sum in a matrix M of size (N,nt) where N is the index up to which you want to sum and nt ...

4 days ago | 1

| accepted

square matrix containing Chebyshev polynomials becomes singular when its size becomes greater than a certain value
t0 = 0; tf = 4; N = 75; syms x h = chebyshevT(0:N, x); A = zeros(N+1,N+1); d = zeros(N+1,1); for c=1:N+1 d(c,1) = ...

5 days ago | 1

| accepted

I was calculated using the Simpson 1/3 rule numerical method, why my running results doesn't appear in the command window?
Use ai=((b-a)/6)*(xa+4*(xb)+xc) %main equation instead of ai=((b-a)/6)*(xa+4*(xc)+xb) %main equation clear all; clc; %in...

5 days ago | 0

Laplace with Heaviside step function solving with ode45
You try to access Y(3), but you have only two differential equations for Y(1) and Y(2), I guess. And the "Y" must be "y" becaus...

5 days ago | 0

| accepted

How to find roots of a quartic function with unknown constant coefficients?
syms x a p = x^4 + 10.1*a*x^3 + 1.81*x^2 + 9*a*x + 0.81; sol = solve(p==0,'MaxDegree',4) vpa(subs(sol,a,1)) % E.g. for a = ...

5 days ago | 0

Se queda paralizado no corre todo el código y no me dice el error tampoco
Do you see why your code fails ? f=@(x)exp(sin(x))-x; f(-1) f(2) x=-1:0.01:2; plot(x,f(x)) You must start with two points ...

5 days ago | 0

Warning: Solutions are parameterized by the symbols: [z, z1], z1.
The "solution" you obtain with the code from above is just a repetition of your equations. Use instead clc clear V1 = 480 ; ...

5 days ago | 0

| accepted

Generate a group of random number
Maybe you mean a Truncated Normal Distribution: https://uk.mathworks.com/help/stats/prob.normaldistribution.truncate.html

6 days ago | 0

How to make a 2 parameter Generalized Pareto distribution? steps required
Use https://uk.mathworks.com/help/stats/makedist.html

6 days ago | 0

finding the solution of a matriciel Differential Equation
Your equations cannot be solved analytically using "dsolve". Use a numerical solver instead: J=0.024; p=2; f=50; ws=2*pi*f...

6 days ago | 0

I try to calculate the following integral
Wolfram Alpha gives an answer in terms of the Meijer G-function: https://www.wolframalpha.com/input?i=integration&assumption=%7...

6 days ago | 1

| accepted

Issue in solving two Non Linear Simultaneous Equations with multivariable function to optimize.
Give z a numerical value and solve for x and y using MATLAB's "fsolve".

7 days ago | 1

| accepted

Do not understand how to make my index exceed 1. (thank you)
In the first line of the for-loop, you set bstress to a scalar value. So in the statement if bstress(i) < NegEstress(i) bst...

8 days ago | 0

Error using vertcat Dimensions of arrays being concatenated are not consistent.
Maybe you mean something like this. I don't know whether it must read y(1) or y(2) at the place marked in bold letter in the ne...

8 days ago | 0