Answered
Solve a complex differential equations system
The main problem with your equations is that they involve a term that has to be evaluated at a boundary point. Otherwise, you co...

9 days ago | 0

Answered
an ode with arguements
You have to define your vector of solution variables as y(1) = f, y(2) = f', y(3) = f'', y(4) = T, y(5) = T' and your function...

9 days ago | 0

Answered
How to invert a square matrix using Gaussian elimination
The newton update is x_(n+1) = x_n - Df^(-1)*f, not x_(n+1) = x_n + Df^(-1)*f. But you should not explicitly compute the ...

10 days ago | 1

Answered
Find Eigenvalues of ODE45 Solution MATLAB
Your system reads z1'= z2 z2' = ( F-(c1+c2)*z2-( ((k1*gamma1+k2*gamma2)*z1^2+k1+k2)*z1+(-k2*gamma2*z1^2-k2)*z3 ) )/m1 z3' = z...

10 days ago | 1

| accepted

Answered
How to get an expression for a Hypergeometric function with symbiotic variable
MATLAB is not able to find the Inverse Laplace transform of such a complicated function as an analytic expression.

10 days ago | 0

| accepted

Answered
can someone please help me coding this saturation equations in matlab
m, umax and u have to be defined previously. psi = zeros(m,1); idx = abs(u) > umax; psi(idx) = sign(u(idx)).*min(abs(u(idx)),...

10 days ago | 0

| accepted

Answered
variable problem of GA
t=[0.015 0.01 0.009 0.012 0.016 0.014 0 0]; w=[0.005 0.004 0.003 0.004 0.006 0.004 0 0]; options = optimoptions( ... 'ga'...

10 days ago | 0

| accepted

Answered
fmincon solution does not differ from initial guess if I provide gradient
Use SpecifyObjectiveGradient Gradient for the objective function defined by the user. See the description of fun to see how to...

10 days ago | 0

Answered
When using integral function to calculate MeijerG function, Matlab will get stuck.
meijerG has a division by 0 at SNR = 0. If you are sure the integral exists at SNR = 0, start with a small value > 0, e.g. aver...

11 days ago | 0

| accepted

Answered
Set answers of first BVP as new boundary condition for second BVP
"value_at_1" is defined in the script part of your code, but it's not automatically visible in the functions you define. Either ...

11 days ago | 0

Answered
lsqcurvefit can't get to the right values
It seems that a variation of your parameters has almost no effect on epsilon_equation. This makes lsqcurvefit assume it cannot m...

12 days ago | 0

Answered
cumprod fuction in GA
Note that Nb was not defined in your code - I added it to the known arrays. rng("default") t=[0.015 0.01 0.009 0.012 0.016 0.0...

13 days ago | 0

| accepted

Answered
cumprod fuction in GA
Your call to ga is wrong: x(1), x(2) and x(3) do not belong there, idx is undefined, lb and ub have 2 elements instead of 3, [...

13 days ago | 0

Answered
if number of steps is not multiple of 3 how to do simpsons 3/8 rule? why im getting more error in simpsons 3/8 rule than in simpsons 1/3 rule?
if number of steps is not multiple of 3 how to do simpsons 3/8 rule? The 1/3 rule can be used for the remaining subintervals wi...

15 days ago | 0

| accepted

Answered
showing error " Array indices must be positive or logical values"
lambda=sigma.*a.*((sqrt(1+32.*theta.*r)./(sigma(i).*a))-1) instead of lambda=sigma.*a((sqrt(1+32.*theta.*r)./(sigma(i).*a))-1)...

15 days ago | 1

Answered
how to format the codes to compute the differential-algebraic equations using ode15s?
I don't see a way to use a MATLAB ode integrator to solve your system. Take a look at http://www.unige.ch/~hairer/software.htm...

15 days ago | 0

Answered
How to write a Matlab code for a sequence of functionals and their minimums
Your code: number_of_iterations = 3; A = @(alpha) ...; % Your NxN matrix A depending on alpha u = ...; % Your Nx1 ...

16 days ago | 0

| accepted

Answered
change the value of a parameter Lambda at each time step
% Experiemental data on 12 months time = 1:12 ; % experimental time 12 months Yc = [20 18 19 24 28 26 25 24 20 1...

16 days ago | 0

| accepted

Answered
Symbolic solution is too long
Did I take the wrong approach in solving this system of differential equations? It depends on what you want. If you want a gen...

16 days ago | 0

Answered
Solve function is unable to find an explicit solution
If you only want one possible solution, use x = solve(f,[T,L]) If you remove your assumptions, you get the general form of the...

16 days ago | 0

Answered
How can I fix "Index in position 2 exceeds array bounds" in for loop?
When you set b = a(1,1) , a is undefined in your code from above. Further, b is a scalar value, namely b = a(1,1). When you ...

16 days ago | 0

Answered
How can I analyze the sum and product together in a code?
rng("default") N = 10; mu = 1; alpha = rand(1,N); alphap = cumprod(alpha); fak = factorial(0:N); terms_numerator = alphap....

16 days ago | 0

Answered
Couple ODE System not enough Input arguments, Why?
If all boundary conditions are given at x = 0 as in your case, you have an initial value problem instead of a boundary value pro...

16 days ago | 1

Answered
Using of cumprod fuction
Tb=1.2; Hb=[2.8 2.2 1.7 1.2 0.8 0.6 0 0]; Sb=[25 28 32 36 35 38 0 0]; F=[70 50 48 55 80 65 0 0]; Sv=[0 280 200 320 360 380 4...

17 days ago | 0

| accepted

Answered
One program is not running after differentiation
clear all; clc; %%%%% parameter declaration %%% g1 = 10^(-4); g2 = 6; g3 = 0.66; g4 = 0.08; dp = 0; dc = 0; d3 = 0; d4 ...

17 days ago | 0

Answered
Graphing partial sums of a series
x = -5*pi : 0.01 : 5*pi; S1 = zeros(size(x)); for n = 1 : 100 S1 = S1 + 2/(2*n-1)*sin((2*n-1)*x)-2/(2*n)*sin(2*n*x); end...

17 days ago | 1

Answered
The sufficient and necessary conditon of fmincon funciton can find out the global optimal solution but not some other local optimal solutions
The answer is: there is no necessary and sufficient condition for "fmincon" to converge to the global optimum. I think it woul...

17 days ago | 1

Answered
How do I use fminunc with two variables?
You tell "fminunc" that you supply the gradient of the objective, but you don't do it. mu = [1, 10, 100, 1000]; tau = 1 ./ mu;...

18 days ago | 0

Answered
Simulation data Fittting problem
Call lsqcurvefit once as dr = @(params,r) (2 * besselj(1, r(:,1). * omega_p) ./ ((omega_m^2 - omega_p^2) * (kappa^2 + omega_m^2...

18 days ago | 0

Answered
Solve Function Doesn't Give All Solutions
Using x = solve(f,[T,L],'ReturnConditions',1) instead of x = solve(f,[T,L]) might help.

19 days ago | 0

| accepted