Community Profile

photo

Torsten


Last seen: Today Active since 2013

Statistics

  • Most Accepted 2023
  • Most Accepted 2022
  • Explorer
  • Master
  • 36 Month Streak
  • Revival Level 2
  • Knowledgeable Level 5
  • First Answer

View badges

Content Feed

View by

Answered
Make this equation periodic (repeating every t_c seconds)
Maybe like this: Q_peak = 1; t_s = 0.1; t_c = 0.3; fun = @(t)Q_peak*sin((pi*t)./t_s).^2.*(t>=0).*(t<=t_s); F = @(t)fun(mod(...

15 hours ago | 0

| accepted

Answered
Optimaloptions doesn't seem to work
You didn't include the "options" setting in the call to "fsolve": x= fsolve(f,[0.01,0.01,0.01,0.01,0.9,0.1,0.1,0.1,10000],optio...

1 day ago | 0

| accepted

Answered
Printing all outputs of the function that has been solved via ode45
Assuming m and h are scalars, use [time_vert,sol_vert]=ode45(@(t,x)endoFlightDeriv(t,x,E,L,PhaseCode),tspan,x0,options) for i ...

2 days ago | 1

Answered
boundary conditions at infinity
You must use a sufficiently large number instead of "Inf" here: x = linspace(0,Inf,100)

2 days ago | 0

Answered
lsqnonlin (lsqcurvefit , fmincon) does not change the variables in an optimization process to find the best fit
We don't know if you get modified values for the array "force" from "ABAQUS" if the input vector "x" to "sim_res" is slightly ch...

3 days ago | 1

| accepted

Answered
DIfferences on Sloped field using 'dsolve' and 'ode45'
The dsolve solution satisfies y(0) = 1: cond = y(0) == 1; the ode45 solution satisfies y(-5) = 1: [u,v] = ode45(f,[-5 5],1);...

3 days ago | 1

| accepted

Answered
How to integrate the Rice distribution and build a graph?
As written, H is an integration variable - you cannot prescribe a value for it since it runs from 0 to Inf. v = 1; sigma = 0.0...

3 days ago | 0

Answered
How to define a binary variable in non linear constraints
Solve two problems: One with x(1)+x(2)+x(3)>= 0 x(4)=1 the other with x(1)+x(2)+x(3)<= 0 x(4)=0 and take the best of the...

3 days ago | 0

Answered
why do i get 'off', 'Octave:abbreviated-property-match' error warning in eeglab?
Maybe you set ismatlab = false somewhere, but started in a MATLAB environment ?

4 days ago | 0

Answered
Optimisation for 3-element Windkessel Model Not Working - Using Least Squares Method and fminsearch. Advice? Should I use other optimisation algorithms?
I'd try to continue with the code below. It seems that a variation of your initial parameters does not cause a change in P suc...

4 days ago | 0

| accepted

Answered
problem of 2d PDE animation
g = 'squareg'; b = 'squareb3'; c=1;d=1;a=0;f=0; [p,e,t]=initmesh(g); x=p(1,:).';y=p(2,:).'; u0=atan(cos(pi*x)); ut0 = sin(...

4 days ago | 0

| accepted

Answered
Error With Least Squares Approximation
Besides the fact that it's numerical nonsense to fit a polynomial of degree 20 to data: What do you get if you simply use coef...

5 days ago | 0

Answered
Failure in initial nonlinear constraint function evaluation. FMINCON cannot continue.
Most probably you mean c(i) = -(((X(i) - x_curr)/sqrt((X(i) - x_curr)^2 + (X(i+n) - y_curr)^2 )) * X(i + 3*n) + ((X...

5 days ago | 0

Answered
Initial Conditions for Newton Raphson Method for 9 equations 9 unknowns problem set
It's the same behaviour with "fsolve", MATLAB's nonlinear solver. The seven equation problem is solved without problems, and th...

6 days ago | 0

Answered
How to assign outputs of a function to an anonymous function in order to optimize with lsqcurvefit
What hinders you from using the usual coding like this ? % test data xdata = ... [0.9 1.5 13.8 19.8 24.1 28.2 35.2 60.3 74.6...

6 days ago | 1

Answered
This is a macroeconomic expression under the topic of real rigidities in long run
syms W_i P nu L n m p sigma real omega = (W_i/P-nu)*L/n*(m^p*W_i/p)^sigma simplify(diff(omega,W_i))

7 days ago | 0

Answered
intergration of function failed to calculate
syms X1 a0 a1 a2 a3 a4 a5 a6 L EI yApprox = a0 + a1*X1 + a2*X1^2 + a3*X1^3+ a4*X1^4 + a5*X1^5 + a6*X1^6; y1Approx= diff(yApp...

7 days ago | 0

| accepted

Answered
Chemical reaction model in accompany with CFD in Matlab
MATLAB is not the suitable tool to solve CFD problems. Use ANSYS or something similar for this. Usually, these tools already hav...

7 days ago | 1

Answered
matlab guide for Calculating 6 dimensional numerical integral Dosen't work
tmax in Q1 must be a scalar, not a function handle. Try "integralN": https://uk.mathworks.com/matlabcentral/fileexchange/47919...

9 days ago | 2

Answered
Solving a system of differential equations with a variable stored in an array
This is what you get with your equations and your data for beta: T = 0:30:360; b = [0.50, 0.49, 0.45, 0.33, 0.27, 0.32, 0.37, ...

9 days ago | 0

Answered
Newton's Method on MATLAB for Stationary Solutions for the Non-linear Klein-Gordon Equation
All you see in the graphs are floating point errors. Your system of equations has solution x(i) = 0 for 1 <= i <= numBases and...

10 days ago | 0

| accepted

Answered
Defining a time-dependent boundary feature
https://uk.mathworks.com/help/pdf_doc/pde/pde.pdf Chapters: Specify Boundary Conditions > Nonconstant Boundary Conditions Sp...

10 days ago | 0

Answered
How to write a Monte Carlo Simulation?
ps = 120; pb = 30; Profit = @(q,D) ps*min(q,D)-pb*q; number_of_trials = 1000000; expected_profit = zeros(301,1); for i = 0:...

10 days ago | 0

| accepted

Answered
This is an iterative program, but the result is wrong. Why?
g = @(x) cos(x); xc = fpi(g,1,1e-6) g(xc) function xc = fpi(g,x0,tol) xold = x0; error = 2*tol; while error > tol ...

10 days ago | 0

Answered
Solving simple integro-differential equation using dsolve in Matlab
If you insert the line simplify(diff(x,t)+2*x+2*x*t) you will see that this expression turns out to be equal to 0. So MATLAB i...

10 days ago | 0

Answered
Integrating the density function of Brownian motion
Maybe it helps to resolve the integration with respect to t: syms t T real positive syms x real g = 1/sqrt(t)*exp(-x^2/t); i...

11 days ago | 0

Answered
Helmholtz problem in circular disk
According to your code, data(i,j) is a zero of besselj(j-1,x) in the interval [(i-1)*pi i*pi]. So let's plot besselj(1,x) and b...

12 days ago | 1

Answered
How to build a graph using stem for a given equation?
Since your delta function does not support array inputs, you must use something like x1=a1*arrayfun(@(n1)delta(n1-b1),n1) inst...

12 days ago | 1

Answered
How do I code a Hamiltonian Cycle in an undirected weighted graph?
I didn't test it yet, but maybe this one from the File Exchange: https://uk.mathworks.com/matlabcentral/fileexchange/51610-hami...

12 days ago | 0

Answered
Find critical points of parametric function
The critical points are solutions of a polynomial of degree 6 in z. There is no solution formula for roots of polynomials of deg...

12 days ago | 1

| accepted

Load more