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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...

6 months ago | 1

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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....

6 months ago | 0

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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 ...

6 months ago | 0

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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...

6 months ago | 2

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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...

6 months ago | 4

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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...

6 months ago | 1

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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,...

6 months ago | 0

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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...

6 months ago | 0

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Cap Maximum ODE solve time
Josh Meyer's answer shows you one possible way to do this: https://uk.mathworks.com/matlabcentral/answers/511547-possibility-to...

6 months ago | 1

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Please help me to plot surface figure. I want to draw this attached photo 2 dimension of (NG,etta) in 3 dimension as (NG, R,etta)
proj() function sol= proj clc;clf;clear; global n; global s %Relation of base fluid rhof=997.1*10^-3;kf=0.613*10^5;cpf=4...

6 months ago | 0

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Answered
How do I delete specific parts of a graph
The arclength of a function will always be increasing. Thus your graph cannot be the arclength of a function. clear, clc syms ...

6 months ago | 1

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Answered
How can I calculate the power spectral density of a gaussian pulse?
Here is another one: https://uk.mathworks.com/matlabcentral/answers/169376-power-spectral-density-two-approaches

6 months ago | 1

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Answered
Please help me. I want to run this attached simple code
Use function dy= projfun(x,y) and replace m by x in the function. Further, b5 and a are undefined. Further, you miss a multi...

6 months ago | 0

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Answered
Positive Roots of bessel functions.
As I understand your question, given l, you try to find 0 < x_1 < x_2 < x_3 < ... < x_m that makes J_l(x_i) = 0 for i = 1,2,......

6 months ago | 0

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Can we find derivative of bessel functions in matlab directly?
You can compute it symbolically first and insert the result as a numerical expression in your code. syms x diff(besselj(0,x),x...

6 months ago | 0

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Answered
Problem with fit Model with odd order polynomial
In the case of the polynomial of degree 5, the design matrix is rank-deficient: T = readmatrix("DistortionTab...

6 months ago | 0

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Doubt of Linear Algebra self-paced course
Why don't you copy it from the course and use it in future ? Or use "quiver" resp. "quiver3": figure(1) quiver([0,0] ,[0,0], ...

6 months ago | 0

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Answered
How to use arrayfun with built-in Matlab functions where the variable parameter is passed with 'Name', 'Value'?
x=[ 6.9100 6.1800 6.0500 5.7900 5.5000 5.2400 4.9800 4.6800 4.5100 4.6191 5.2582 5.9801 6...

6 months ago | 0

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Answered
MNPBEM Error - Issue with dot product in tripolygon file
The variable "edge" does not seem to have a substructure with name "pos". E.g. s = 2; s.pos will give this error message. ...

6 months ago | 0

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Please help me to run this code
Note that you plot y(1,:), not y(6,:). If I were you, I'd simply use "plot" to compare the three curves depending on Gr. proj(...

6 months ago | 0

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Answered
Convert a decimal approximation to exact value symbolically
Here, you need the fact that y2-y1 is an odd function: syms x y y1=sin(pi*x/2); y2=x; x1=-1; x2=1; A=2*int(y2-y1,x,x1,0)

7 months ago | 0

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Answered
solving system of equations
This works, but I doubt it will work in all possible cases. % Tolerance for convergence check tol = 1e-8; max_iter = 100; it...

7 months ago | 0

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first order PDE , verification of one solution
You shouldn't waste your time here with symbolic manipulations. What is important is that solutions f(x,y) of the PDE df/dx + ...

7 months ago | 0

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Interp1 is not working after applying unique because of rounding off
https://uk.mathworks.com/help/matlab/ref/uniquetol.html

7 months ago | 0

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Answered
(Error using vertcat) Dimensions of arrays being concatenated are not consistent
x and y are of size 1x500, phix(:,a)' and phiy(:,a)' are of size 1x8. So either x and y had to be of size 1x8 or phix(:,a)' and ...

7 months ago | 1

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Symbolic integration: error
Here is one possible implementation: syms x y r u = ((x-1+r)^2+y^2-r^2)*(y^2-r^2/(1-2*r)*x^2); du = gradient(u, [x,y]); du2 ...

7 months ago | 0

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Change ode time step based on state
An easier way is to choose appropriate absolute and relative tolerances to reduce the error of the integration: options = odese...

7 months ago | 0

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Odefun returns a vector of length 1, but the length of initial conditions vector is 4.
Use function ydot = noMoonGrav(t, y) instead of function [t, ydot] = noMoonGrav(t, y)

7 months ago | 1

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Answered
Symbolic calculation with solve command
Use S = solve(eqns,[k1 k2 k3],'MaxDegree',4) instead of S = solve(eqns,[k1 k2 k3])

7 months ago | 1

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Answered
Display data in a while loop as a table
clear, clc format longg f=@(x) x^3-5; df=@(x) 3*x^2; [n,X,Y] = newtonimproved_4_7(f,df,1,0.00001); t=table((1:n).',X',Y'); ...

8 months ago | 1