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Torsten


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Answered
PDEPE boundary condition outputting odd results.
function main m = 0; tspan = linspace(0,365*20*86400,21); xmesh = linspace(0,20,201); sol = pdepe(m,@pdefun,@icfun,...

1 day ago | 0

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Answered
---- ------- ---- ------
format long I = 0.0; Iexact = 0.904524237900272; eps = 1e-15; n = 0; while abs(I-Iexact) > eps I = I + (-1)^n/(factorial(...

1 day ago | 0

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Answered
Generate random number from a two-parameter exponential distribution
gam = ...; lambda = ...; n = 100; x = gam - log(1-rand(n,1))/lambda give you 100 random numbers distributed according to you...

2 days ago | 0

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Answered
how to run optimisation problem
Use fmincon with objective function f = @(x)(R'*x)/sqrt(x'*sigma*x) and linear constraint Aeq = ones(size(x)) beq = 1 Best...

2 days ago | 0

Answered
How to take the fourth derivative of a reflectance graph
If you have the signal processing toolbox licenced, use "sgolay" and "sgolayfilt". Or download from the file exchange: https:/...

2 days ago | 0

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Answered
Saving all the variables from an ode45 Function
[tw1,yw1] = ode45('Newscript_VectorField',Timet1,Ic1,options) w = yw(:,1)*Yi11 + yw(:,2)*Yi12

3 days ago | 1

Answered
How to automatically constrain some of the unknown values in an optimization problem?
If you know in advance which elements of the x-vector are grouped together, you can simply use Aeq and beq to define the equalit...

3 days ago | 1

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Answered
Too many input arguments - Fminsearch
function fmin x0=0; %parâmetro de valor inicial para a condição options=optimset('Display','iter','TolFun',0.1) [x]=fmi...

4 days ago | 0

Answered
Error in while loop
Do you want a different value for B for each minor, i.e. B(i) instead of B ? Then use function IsStable(polynomial) if AllNon...

4 days ago | 1

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Answered
Combining vectors [1 2 3 4 5] and [2 3 4 1 5] to [12 23 34 41 55]
v = 10*v1 + v2

4 days ago | 0

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Answered
Set up an OR argument for equation
v = (xdot_1-xdot_2)).*(sign(x1-x2-gap)+1)/2; if v > 0 fp = (k_inp*(x1-x2-gap)+c_inp*(xdot_1-xdot_2)).*(sign(x1-x2-gap)+1)/2 ...

5 days ago | 1

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Answered
distance between two points
You mean "where each row indicates the XYZ coordinates of a point" ? And you want to calculate the distance between the correspo...

8 days ago | 1

Answered
Correct formulation for a fmincon problem
The vector of unknowns for fmincon will be Uvec = [u1(t0),u2(t0),u3(t0),u4(t0),u5(t0),u1(t2),u2(t2),u3(t2),u4(t2),u5(t2),...,u1...

8 days ago | 0

Answered
ode45 code not running and need help imputing my boundary conditions
function main y0=zeros(7,1); y0(1) = 0; % f y0(2) = 0; % f' y0(3) = 0; % f'' y0(4) = 0; % theta y0(5) = 0; % theta' ...

8 days ago | 1

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Answered
How to generate random orthogonal codes in matlab
mat2str(de2bi(randi([0,3],5,16)))

9 days ago | 0

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Answered
plotting profiles from differential equations
function dFTdV = Reactor3(V,FT) %Reactor3 function is used to obtain mass and energy balances across the %reactor F = FT(1...

9 days ago | 1

Answered
How to calculate the distance
distmat = B(:,4:7)-repmat(A,4,1); dist = vecnorm(distmat.')

10 days ago | 1

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Answered
trouble in integral solving [SOLVED]
q = vpa ( int(fun,[-Inf Inf]) )

10 days ago | 0

Answered
splitting real and imaginary part of a complex equation in order to generate two nonlinear equations to solve for two unknown real constants
Z0 = 50; Y0 = 1/Z0; e_inf = 4.6; % optical permittivity at high frequencies e_s = 78.3; % static permittivity ...

10 days ago | 0

Answered
"The boundary condition function BCFUN should return a column vector of length..." ERROR USING BVP4C
As initial condition, you give a row vector of ones of length 432. So in ex1ode, bvp4c will give you a vector of length 432 for...

10 days ago | 1

Answered
Finite Integral with periodic values of x
idx = (x>=0.3 & x<=4.5); xp = x(idx); yp = y(idx); F = cumtrapz(xp,yp); F = F(end) - F; plot(xp,F)

11 days ago | 1

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Answered
Integration within particular range
idx = x>=2 && x<=3; xp = x(idx); yp = y(idx); value = trapz(xp,yp)

11 days ago | 0

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Answered
Solve symbolic Sylvester-like equation
syms a x11 x12 x21 x22 b11 b12 b21 b22 A=[a+sym('1'), sym('2'); sym('3'),sym('1')]; X=[x11,x12;x21,x22]; B=[b11,b12;b21,b22];...

11 days ago | 0

Answered
speed for loop in sum
function main x = linspace(-2,2,100); %some vector [X,XX] = meshgrid(x,x); %some matrix k = 0:20; a = 0.5; A0 = a...

12 days ago | 1

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Answered
How to use lognrnd?
It is common to say that X is lognormally distributed with parameters mu and sigma if it has the pdf f(x) = 1/(x*sigma*sqrt(2*p...

12 days ago | 0

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Answered
Numerical value for sum of bessel functions
k = 0:10; x = 3; A0 = sum((-1).^k.*x.^(2*k).*besselj(2*k,x)) If x is a vector, use A0 = arrayfun(@(x)sum((-1).^k.*x.^(2*k)....

12 days ago | 1

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Answered
System of differential equations and fitting with lsqcurvefit
function main % loading Exp data CurrentDensity = xlsread('Modified_Current_density_all','Sheet1','A1:J1001'); Brightne...

12 days ago | 0

Answered
HOW TO SOLVE TRANSCENDENTAL EQUATION
function main Enle0 = 1.0; Enle = fzero(@fun,Enle0) end function res = fun(Enle) Vc = 0.249; c = 3e8; m0 = 0....

12 days ago | 1

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Answered
Finding the 'n'-th derivative of a function containing 'n'
syms x k n = 10; diff(exp(-x)*x^(n+k),x,n)

15 days ago | 0

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Answered
how to create an vector contains 10000 random values that uniformly distributed with mean 1 and variance 10 ?
mean = 1.0; std = sqrt(10); N = 10000; u = (mean-sqrt(12)/2*std) + sqrt(12)*std*rand(N,1) u is uniformly distributed on [a:...

16 days ago | 0

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