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# Stephan

##### Last seen: Today
1.159 total contributions since 2017

Knowledge means knowing where it is written...

Interested in:
- Optimization
- Mathematical Modelling
- Improvement of my programming skills

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Environment Reinforcment learning Matlab
See this link to the documentation: https://de.mathworks.com/help/reinforcement-learning/ug/create-custom-reinforcement-learnin...

1 dag ago | 0

Custom Environment for Reinforcment learning
There is a step-by-step example in the documentaion: https://de.mathworks.com/help/reinforcement-learning/ug/create-custom-rein...

1 dag ago | 0

You need to perform a inverse laplace transformation: num=134; den=[1 16 134]; x=tf(num,den) subplot(1,2,1) step(x) title(...

3 dagen ago | 1

write function that generates an echo to audio
Hi Franziska, there is no need for loops: % Load sample sound load TestSoundEcho.mat; % Play sample sound sound(data, fs)...

3 dagen ago | 0

Output a solution for a function at a specific value input
magT = @(omega)sqrt((5.903*10^24)^2+(1.181*10^20*omega)^2)/sqrt((1.181*10^25-(2.361*10^16*omega^2))^2+(9.445*10^20*omega)^2); ...

3 dagen ago | 0

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solving integral in matlab
What you are looking for is an analytical solution. The integral function does solve numeric. To solve symbolic use int as John ...

3 dagen ago | 1

Split data into groups
A = randi(5000,300,1); % random data A = sortrows(A); % sort it low = A(1:100); % just use indexing now mid = A(101:200); hi...

4 dagen ago | 0

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Syntax error when opening a file using a path. it says " use a newline, semicolon, or comma before this statement "
It is unclear what you want: maybe you forgot to underline your variable name function_data = angleAnalysis_withPlots('C:/rese...

4 dagen ago | 0

HELP: looping a function and plot (ode23)
tspan1 = [0, 4]; tspan2 = [4, 10]; y0 = [0, 0]; [t1_r1, y1_r1] = ode23(@(t,y) fun(t,y,0.5,5), tspan1, y0); [t2_r1, y2_r1] ...

4 dagen ago | 1

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problem with table / array/cell
Your table content is a cell array - Read the Tips section from the documentation. It tells you why and how to deal with it. ce...

4 dagen ago | 0

Solve ODE with BC
I doubt that your ode has an analytical solution - however here is a minimal working example of how to include BC's in a symboli...

4 dagen ago | 0

Respective matrices for different sheets in imported file frin excel
Use the 'sheet' option like shown here: https://de.mathworks.com/help/matlab/ref/readtable.html#d120e1047964 contentTable = rea...

4 dagen ago | 0

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I'm trying to integrate, but I get an "undefined function" error.
int does not accept numerical inputs, because it performs symbolic integration - so you have to define a numerical vector for t ...

4 dagen ago | 0

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Error using vertcat Dimensions of arrays being concatenated are not consistent. For solving ODE
tspan = [0 60]; %Initial Value C_V0 = 0; %x(1) C_I0 = 0; %x(2) C_C0 = 2; %x(3) C_W0 = 0; %x(4) C_G0 = 0; %x(5) [t,x] ...

4 dagen ago | 1

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calling a variable in another function
function [LookupTableFiles]=getaerotablelisting( FilePrefix, DirectoryName , filetype ) FileList = dir('DynamicData...

7 dagen ago | 0

Easily solved equation isn't being solved by 'solve'
There are 3 solutions, which you will find by setting the 'ReturnConditions' option to true: syms x A alpha h2m syms b positiv...

9 dagen ago | 1

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Undefined function 'ln' for input arguments of type 'double'. Sorry I kindly no idea what was wrong with the coding. Kindly help please ,Thanks a lots.
Change: F = inline('y*log(y))','x','y','z'); to: F = inline('y*log(y)','x','y','z'); also remove the error on the last line ...

10 dagen ago | 0

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Nonlinear system of equations
https://de.mathworks.com/help/optim/ug/fsolve.html function myEq b1=1000; b2=100; c=50; t=0.76; T=950; n=5; x0 = [1 1 ...

10 dagen ago | 1

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Error using GPU in Matlab 2020a for Reinforcement Learning
If you install Update 2 the problem should be solved: https://de.mathworks.com/support/bugreports/?release=R2020a&release_filte...

15 dagen ago | 2

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Submitted

Calculates values for Directional Movement System like J. Welles Wilder describes in his book 'New Concepts in Technical Trading...

How to remove 'e' from a matrix?
N(N<1e-8)=0; this will hard set all values smaller than 1e-8 to zero. >> format shorte >> N = [12, 0.24e-16, 9] N = ...

ongeveer 2 maanden ago | 0

Solving System of 4 Non-Linear Equations
fsolve is a numerical solver - use vpasolve instead: syms A B C t0 eq1 = A*sin(2*B*pi*0.2 + 2*B*pi*(0 - t0)^2)+C - sin(2*pi*0....

ongeveer 2 maanden ago | 0

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How to concatenate horizontaly and not vertically
use C = [C, RAIES]; V = [V, DATAS]; instead C = [C; RAIES]; V = [V; DATAS];

ongeveer 2 maanden ago | 1

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How to use ode45 to model malaria?
tspan = [0 100]; y0 = zeros(1,4); [T,Y] = ode45(@malariaSEIRS, tspan, y0); figure(1) plot(T,Y) grid legend('S', 'E', 'I'...

ongeveer 2 maanden ago | 0

Iam getting an error with the ODE45 function (line 90)and (line 115)?
clc clear y0=[0.01 0.5]; %enter the initial conditions. t0=[0 60] ; %enter the first and final time for the analysis. [t,x]=...

ongeveer 2 maanden ago | 1

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insert zeros into vector
a = [1 2 3 4 5] b = zeros(4,numel(a)) result = reshape([a; b],1,[])

ongeveer 2 maanden ago | 1

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I need help as soon as possible
Try to work with a table to make life easier: N=1:10; a=0;b=2;alp=0.5; f=@(t,y)y-t^2+1; yexact=@(y,t)(1+t).^2-0.5*exp(t); h...

2 maanden ago | 2

Convert two vectors (x and y) to a square matrix ?
x = 0:0.01:6.28; y = sin(x); M = ones(size(x,2)); x_int = 1:size(x,2); y_int = ceil(y * size(y,2)/(abs(min(y))+abs(max(y...

2 maanden ago | 1

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Fit to find the value of an unknown parameter
Try to optimize with least squares: A=0.1; B=0.5; C=100; % Range for H lb = 0.0001; ub = 0.05; best_H = fminbnd(@(H)s...

2 maanden ago | 0

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