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how can I solve this non linear partial differential equation mentioned below I have some initial & boundary condition
Discretize the differential operators, include the boundary conditions and solve the resulting system of nonlinear equations for...

4 years ago | 0

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Solving Constrained Optimization for 4 variables (or 3?)
It's a simple linear optimization problem. If you are allowed to, use "linprog" to solve. f = [1; 1; 1; 0]; Aeq = [3 1 0 -1;1 ...

4 years ago | 1

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Solving a set of simultaneous equations
a = 0.5; fun =@(x1,x2,x3,x4) [x1^2 + a*x1*x2 + a*x1*x3 + a*x1*x4 - 30^2;... a*x2*x1 + x2^2 + a*x2*x3 + a*...

4 years ago | 1

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How to customize a complex differentiated equation?
The term is 0 if r^2+e3*G*H**x^4e2-f^3*b = 0. Can you solve for x ?

4 years ago | 0

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Numerical Integration on Matlab
I2 = integral(@(xint) ((xint*I1_c*I2_c)/2.*xint),xi_0,xi_1); J2_c = (1-epsilon*tan(phi))*(cos(phi))^2; J2 = integral(@(xint) ...

4 years ago | 0

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Exprnd function same randomness after a loop
https://de.mathworks.com/matlabcentral/answers/269639-what-does-command-rng-default-do

4 years ago | 0

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how to do series summation of complex triple integral?
I suggest Er = 4; E0 = 8.85418782e-12; %F/m b = 5e-3; %mm --> m a = 2e-3; %mm --> m d = 150e-6; %um --> m %% Capacitance ...

4 years ago | 1

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Saving FOR loop values to an array
T = 0:resolution:BurnTime; nt = numel(T); for i = 1:nt t = T(i); BurnRate = (-(MFuel)/BurnTime); CurrentMass = ...

4 years ago | 0

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How to use syms in multiple variable?
This code does not throw an error, but I don't know whether it will succeed to find an antiderivative for your expressions. sym...

4 years ago | 0

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How to remove "root(f(z), z, n)" from solve solution?
syms f B r L k c g t S u v h m w J a n p V D A mu q m1 m2 m3 eq1 = (f*B + r*L - k*L - c*L - m1*A*L) eq2 = (g*B + t*S - u*S - v...

4 years ago | 0

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linear least regression solving a and b from given data
b = a0/a1 instead of b = a0

4 years ago | 0

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I have simultaneous nonlinear multi inequality problem with constraints and parameters.
What do you expect as output from the solve command ? You can multiply the last inequality by beta and it cancels out. So beta...

4 years ago | 0

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How do I plot a multivariate piecewise continuous function?
Why don't you write a simple function for F with 4 if-statements for the 4 cases ? function value = F(x,y) if x ... && y ......

4 years ago | 0

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Solving a 6th order non-linear differential equation in Matlab
I think that nobody in this forum will dive into selfmade software if there are well-tested MATLAB alternatives. So these few l...

4 years ago | 1

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Periodic Boundary Conditions with pdepe
It is possible to use PBC with pdepe? No, sorry.

4 years ago | 0

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Algorithm / Function to find weighting of parameters how influens on result
Seems exactly the opposite from what you presume is true: w = [5 4 9;2 3 0]\[80;30] [0 0 9;10 10 0]*w

4 years ago | 0

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function input to solve ODE
% solve u'(t) = F(t,u(t)) where u = [u1(t), u2(t), u3(t)]' % using forward euler method % Initial conditions and setup neqn...

4 years ago | 0

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I want to simulate the following programme on pdepe solver with third type inlet boundary of Heaviside nature with t0 = 140 days and a zero flux ourlet boundary
pl = ul - C0 * ( 1 + exp(-2*k*t0) )/( 1 + exp(2*k*(t-t0)) ); ql = 0.0; I suggest you plot the function f(t) = C0 * ( 1 + exp...

4 years ago | 0

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Subtraction between a matrix and a column vector
B = A - x where A is your matrix and x is your vector.

4 years ago | 1

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Having problem with a infinite double sum
You might want to try a numerical solution: a = 2.0; b = 4.0; nu = 20; q0 = 1.0; X = linspace(-2*pi,2*pi,250); Y = linspac...

4 years ago | 1

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Trigonometric functions using dsolve
fun = @(t,theta) [1+sin(theta(2))-theta(1);1+theta(3)-theta(2);theta(2)-theta(3)]; theta0 = [0.1, 0.3, 0.2]; tspan = [0,2*pi] ...

4 years ago | 0

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convert matrix to array
A = A(:)

4 years ago | 0

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Not enough input arguments from a row vector
function x = myquad(vec) a = vec(1); b = vec(2); c = vec(3); if b^2 - 4*a*c > 0 x = 2; else if b^2 - 4*a*c =...

4 years ago | 1

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How can I define a lower bound of the LP?
A = [1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;... 0 0 0 0 0 0 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ...

4 years ago | 0

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Can this be integrated within MATLAB?
syms XC0 beta zeta f = XC0*zeta*(zeta+sym('1e-9'))^2/(zeta+sym('1e-9')+beta*XC0)^2 intf = int(f,zeta,0,1) Output: 2 ...

4 years ago | 0

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Solving a highly non linear equation in Matlab
It's "only" an ODE of degree 6. Rewrite it as a system of first-order ODEs. You will need 6 initial or boundary conditions. De...

4 years ago | 0

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How can I resolve this problem?
The arrays "Ppost" and "ex" don't have the same number of elements. This has the effect that "ex" has less elements than the v...

4 years ago | 1

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reordering matrix elements according to another matrix
[A,index] = sortrows(A) B = B(index,:)

4 years ago | 0

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error with the integral of a imaginary array
L=integral(g,-Inf,Inf,'ArrayValued',true);

4 years ago | 0

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Fitting a curve on normalized histogram
You can directly calculate the distribution of Z from the distribution of X and plot its PDF. Or do you only have a discrete nu...

4 years ago | 0