Community Profile # Torsten

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why do I get this error in the simulation
Before calling "interp1", use % Sort array oxygen_energy_tot in ascending order [oxygen_energy_tot_sorted,idx_sort] = sort(oxy...

3 hours ago | 0

ode45 with a array of vector
a1 = ...; a2 = ...; a3 = ...; b1 = ...; b2 = ...; b3 = ...; c1 = ...; c2 = ...; c3 = ...; vp = ...; tValues = linspace...

3 hours ago | 0

function handle array Problem
result = integral(@fun,0,1000,'ArrayValued',1) function value = fun(a) m = [1,2]; U(3) = a + 2; V(3) = a - 2; for...

9 hours ago | 0

i want to solve a set of homogeneous linear equation
Or use the following code to produce an optimal solution in the least-squares sense: A =1.0e+04*[6.6064,-3.5642,0,0;-3.5642,6.6...

10 hours ago | 0

is there any way to get a 2nd order polynominal through 2 points(each end point)
rng("default") syms a b c x y n = 30; % number of data points xdata = sym('xdata',[1 n]); % x values ydata = sym('ydat...

10 hours ago | 0

Error using plot Vectors must be the same length
As you can see above, S and f have a different number of elements. So they cannot be plotted against each other.

1 day ago | 1

incorrect dimensions for matrix multiplication in piecewise function in matlab
tau = 1.0; V_D = 0.72; vi = @(t) sin(2*pi*t); f = @(t) max(vi(t)-V_D,0).*exp(-t/tau); t = 0:0.01:2*pi; plot(t,f(t))

1 day ago | 0

How do I store an ODE in a vector?
Either you use the code below and work with the time derivatives after the integration to decide when the curves have flattened ...

2 days ago | 0

How to implement the Gaussian radial basis function in MATLAB ?
Before you start the optimization, check whether K in your case is positive-definite. Lt = 10; p = rand(Lt,4); sigma = 1.0; ...

3 days ago | 0

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Interface boundary condition in transient heat problem
Here is a sample code for what I wrote above: % Set parameters x1start = 0.0; x1end = 0.25; x2start = x1end; x2en...

3 days ago | 0

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How to solve below PDE based model using finite difference scheme.
Take a grid (ai,xj) over your rectangular region with 0 = a1 < a2 < ... < an = 60 0 = x1 < x2 < ... < xm = 40 Approximate the...

3 days ago | 2

Error: Array indices must be positive integers or logical values. implementing fletcher reeves method
[xmin,valormin]=fletcherreeves2([5;5],@(x) x(1)^2-x(1)*x(2)+4*x(2)^2+3*x(1)+2,@(x) [2*x(1)-x(2)+3;-x(1)+8*x(2)],10^-(6)) func...

4 days ago | 0

Why do I get 'Array indices must be positive or logical values' in symsum function?
h=0.05; U=0.02; delta_t=1; v=1.846*10^-5; d=1.117; t=50; y=0.2; P=pi; n = 1:300; Fn = 1./n.*exp(-(n.^2*P^2*v*t)/(d*h^2)...

4 days ago | 0

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How to get numerical values of nonlinear implicit function?
k = -1.5; F = @(t,y) log(abs(y)) - y.^2/2 - t - k; fimplicit(F,[0,4],'*') t = 0:0.01:0.99; y0 = 2.0; y = zeros(size(t)); f...

4 days ago | 0

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How to write the equation in matlab I= A A* T² exp (qob/kT) exp (q(V - Rs I /kT)) (exp (-1/n) ? Why is the curve not shown in the drawing?
Maybe you mean I = A*a*T^2*exp(q*phi_b/(K*T))*exp(q*(V-I1*Rs/(K*T)))*exp(-1/n) ?

4 days ago | 0

Solving economic dispatch problem
The message from "quadprog" says that no feasible solution can be found. So you will have to reconsider your constraints - it se...

4 days ago | 0

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it says it cant plot because my vectors aren't the same size but they are
Check whether size(yvar) equals size(xvar). I think this cannot be true because the following code works: yvec=[6.67 17.33 42...

5 days ago | 0

I'm trying to run a code to plot conversion vs catalyst mass in a packed bed reactor, but something is wrong.
You tell the integrator that you have four additional inputs to your function [W,F]=ode45(@(t,F)ODEfun(t,F,T,P_total,F0_total,R...

6 days ago | 0

Bisection function to determine the value of (k) not working.
Please fill in the missing values and try again. If you don't succeed, it usually helps to plot f in the range 1e-12:1-1e-12 fo...

6 days ago | 0

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2nd Order ODE Euler method not producing expected results
Not that bad. %Coefficients m1=3; m2=6; k1=1; k2=9; k3=3; c1=0.02; c2=0.09; c3=0.06; % Step sizes h=0.00005; t...

6 days ago | 0

Index exceeds the number of array elements (7).
The last two loops also have to run from 1 to length(code), not from 1 to length(t).

6 days ago | 0

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Summing over indices using symsum
u=symunit; Q(1)=10E-9*(u.C); Q(2)=15E-9*(u.C); Q(3)=7E-9*(u.C); Qsum = sum(Q)

6 days ago | 1

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Fitting method with multiple response variables (y1, y2, y3).
rng("default") X = linspace(0, 10, 100)'; Y1 = 2*X.^2 - 3*X + randn(size(X))*0.5; Y2 = 2.5*X.^2 - 3*X + randn(size(X))*0.5; ...

6 days ago | 0

sym/besseli - Too many input arguments.
There is no third argument in the symbolic function "besseli": https://de.mathworks.com/help/symbolic/besseli.html

6 days ago | 2

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Symbolic Computations for three non-linear equations solution
fl = [1.883806, 1.883135, 1.882170]*10^9; Qe = [161.43, 10.765, 2.5734]*10^4; syms A fu alpha eq1=fl(1)-(1+(A/(Qe(1)^alpha))...

6 days ago | 1

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i am trying nonlinear for nonlinear ode using by finite difference method
You want to solve a nonlinear system of equations using Newton's method, but you didn't supply the Jacobian "df". i.e. df{i}/dx...

6 days ago | 0

which of the following sets vectors are independent?
In order to prove that sin(t), cos(t) and cos(2*t) are independent, you have to show that if f(t) = a*sin(t) + b*cos(t) + c*co...

6 days ago | 0

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