Answered
Unexpected results using SVD to separate components that make up a function
Others have already explained why you cannot recover p1, p2 and p3 from an SVD of p = p1 + p2 + p3. All you can do is write p...

11 months ago | 0

Answered
How can i get to get this curve in red when the vector is moving? The curve results from the displacement of the tip of the vector
% Définir les vecteurs de la base O (i, j, k) i = [1; 0; 0]; % Vecteur i j = [0; 1; 0]; % Vecteur j k = [0; 0; 1]; % V...

11 months ago | 0

| accepted

Answered
Error plotting orbits figure
Seems that most of the missing functions are available under http://www.rotordynamics.info/ (Software for Lateral Vibrations, ...

11 months ago | 0

| accepted

Answered
Counting the number of increments in a vector
x = 0:0.1:7; numel(x(x<=3))

12 months ago | 0

| accepted

Answered
Get mean of a matrix which has NaN in it
grades = [2,4,6; 5, NaN, 1; 7, 2,NaN] mean(grades,1,"omitnan")

12 months ago | 0

Answered
Resonance in moonpool type structures
I'd change k(n) = lsqnonlin(fun_alpha, guess, x0_left, x0_right); to k(n) = lsqnonlin(fun_alpha, guess, x0_left, x0_right,op...

12 months ago | 0

| accepted

Answered
Incorrect results for subtraction despite working for other use cases.
"segments_of_free_space" and "focal_lengths" (or "f" and "gaps") must have the same number of elements because you reference gap...

12 months ago | 0

Answered
MATLAB Onramp: Help with Plots
The problem seems to be known: https://uk.mathworks.com/matlabcentral/answers/2178891-why-does-my-answer-to-a-task-show-up-as-i...

12 months ago | 0

| accepted

Answered
Help with Solving PDE System with DAE in MATLAB
You have discretized your equations in space. Thus the y variables are only functions of time for fixed z-coordinates. Here is...

12 months ago | 1

Answered
Solving DE initial value problem symbolically in Matlab
By default, y is assumed a function of t: syms x y(t) sol(t) = dsolve('x*Dy+y=-sin(x)','y(pi/2)=0') simplify(x*diff(sol,t)+so...

12 months ago | 0

Answered
How to iteratively solve when equations are dependent on each other.
Sigma_ysrtM = load("Sigma_ysrtM.mat").Sigma_ysrtM; T_oQlast = load("T_oQlast.mat").T_oQ; K_dot_nom = load("K_dot_nom.mat").K_d...

12 months ago | 0

Answered
dispersion equation in water waves
I solve in y = x*h. Thus the result has to be divided by h to get x. k(j,n) = fzero(@(y)fun_alpha(y,omega(j)),y0_alpha)/h; The...

12 months ago | 0

Answered
Difference between integral and cumtrapz.
Your input arguments to "cumtrapz" are reversed: you have to use intfx = cumtrapz(x,fx); instead of intfx = cumtrapz(fx,x); ...

12 months ago | 0

Answered
Please 🙏 help me to find the exact solution of ODE
I doubt you can get an analytical expression for y. All you can do is to transform your 2nd order ODE into a system of first-ord...

12 months ago | 0

| accepted

Answered
Storing value in a matrix from a for loop.
Don't use "size" as a variable name - it's a MATLAB - reserved function: https://uk.mathworks.com/help/matlab/ref/double.size.h...

12 months ago | 0

| accepted

Answered
How to store a matrix so that I can call upon it in any other file I am working in?
Declare the matrix as "global" or pass it as input argument to all functions where it is needed. Or save it as a .mat-file and ...

12 months ago | 1

| accepted

Answered
Gaps in contour plot using custom secant method (when solving for two-plume merger)
The equation for rho is a polynomial of degree 4. The MATLAB function "roots" solves for the four zeros of this equation. I ...

12 months ago | 0

| accepted

Answered
May I ask everyone to help me solve this problem
I'm not sure, but if you want to integrate the normal distribution, use "mvncdf". integral2 can be very inaccurate when integrat...

12 months ago | 0

Answered
Clustering using Gower's Distance
To use a distance that is not implemented, you have to define a function handle. Since I guess that GowerDst is not a function h...

12 months ago | 0

Answered
Why do I get the wrong values for enthalpy on the P-h diagram block in Simulink/Simscape?
The reference enthalpy for R-134a is often given for the saturated liquid at -40°C, with a value of 148.4 kJ/kg. If you look at ...

12 months ago | 1

| accepted

Answered
Problems plotting an implicit solution to a differential equation
For more complicated cases where an explicit solution cannot be found: syms y(x) eqn = diff(y) == (2*x+y+2)/(2*x+y-4); soluti...

12 months ago | 0

| accepted

Answered
fft function seemingly not evaluating correctly
syms x f = 1/(2*sym(pi))*exp(-0.5*x^2); fourier(f) The Gaussian Pulse example under https://uk.mathworks.com/help/matlab/ref...

12 months ago | 0

Answered
mvncdf seems to be violating the additive property of integrals
The complete IR^2 is made up of four quarter zones, not two. Sketch the quarter zones over which you integrate to understand wha...

12 months ago | 1

| accepted

Answered
how to evaluate the integral of the expression involving bessel functions.
l = 0; R_I = 2; N = 3; P = 3; k = [0.28,0.2,0.1,0.05]; %[k0,k1,k2,k3] e = [0.3,0.9,0.7]; %[e1,e2,e3] d = [0.1,0....

12 months ago | 0

Answered
I have 9 coupled nonlinear ordinary differential equations. and i have to convert it in to state space form. here i have 9 state variable including theta.
Write your system as M(U,U')*U'' = f(U,U') with a (9x9) matrix M. Then you can use ode15s to solve the system V' = W ...

12 months ago | 0

| accepted

Answered
Solving boundary value problem
I think this is what you want. But although there are four boundary conditions for four free parameters, they do not suffice to...

1 year ago | 2

Answered
Wierd wiggle in plot of symbolic expression
Using IB0(t) = vpaintegral(@(tau)B(tau,0),tau,0,t,'Waypoints',[1]); instead of IB0(t) = int(B(tau,0),tau,0,t); makes the wi...

1 year ago | 4

| accepted

Answered
How to Apply Multiple BC Types (Dirichlet, Robin, Neumann) on a Single 3D Face?
gd = [3 4 -0.5 0.5 0.5 -0.5 -0.5 -0.5 0.5 0.5; 3 4 0.5 1.5 1.5 0.5 -0.5 -0.5 0.5 0.5; 3 4 -1.5 -0.5 -0.5 -1.5 -0.5...

1 year ago | 1

| accepted

Answered
Solving a system of a changing number of nonlinear equations
The solver doesn't converge. You should check parameters and equations. load 'AppxSteadyStateTestInput.mat' fun = @(x)test1(x,...

1 year ago | 0

Answered
How to Apply Multiple BC Types (Dirichlet, Robin, Neumann) on a Single 3D Face?
Here is one way to create the geometry such that you can set different boundary conditions on different faces at the top. If yo...

1 year ago | 0