Stephan
Last seen: 4 days ago
1,180 total contributions since 2017Knowledge means knowing where it is written...
Interested in:
- Optimization
- Mathematical Modelling
- Improvement of my programming skills
Stephan's Badges
Contribute at least one answer each month for 24 consecutive months
Awarded to Stephan on 03 Apr 2020
Your submissions were downloaded 10 or more times in a month
Awarded to Stephan on 01 Nov 2019
Publish your first comment or rating
Awarded to Stephan on 09 Oct 2019
Publish your first submission
Awarded to Stephan on 09 Oct 2019
Solve all the problems in Introduction to MATLAB problem group
Awarded to Stephan on 28 Jan 2019
Accept 5 answers given by other contributors
Awarded to Stephan on 11 Oct 2018
100 of your answers have been accepted
Awarded to Stephan on 04 Sep 2018
Answer 10 questions that were unanswered for more than 30 days
Awarded to Stephan on 22 Jun 2018
Be the first to solve a problem
Awarded to Stephan on 24 Apr 2018
Create a problem
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Provide your first answer ever to someone else's question
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Awarded to Stephan on 08 Jun 2017
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Awarded to Stephan on 08 Jun 2017
Solve a problem for the first time
Awarded to Stephan on 07 Jun 2017
How to use fsolve when a nonlinear equation given two arrays of parameters (not the variables)? Why can't I use for loop?
Hi, you could try to vectorize your function in order to avoid for loops - here is a simple example: % Constant 1 as a row vec...
6 days ago | 0
Question about GA and the fun.
Have a read here: https://de.mathworks.com/help/optim/ug/passing-extra-parameters.html In your case it should look somehow lik...
6 days ago | 2
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Help me I am unable to input array
They way you coded it needs to enter the single values one after each other: Enter elements of x=1 Enter elements of x=2 Ente...
7 days ago | 0
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Problems using LSTM with PPO Agent - Error: Invalid input argument type or size such as observation, reward, isdone or loggedSignals.
I finally could solve the issue. The problem was that there were 2 LSTM layers in the network, which led to the error: Caused b...
11 days ago | 0
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Question
Problems using LSTM with PPO Agent - Error: Invalid input argument type or size such as observation, reward, isdone or loggedSignals.
Hi, i implemented some RL agents (DQN, AC, PPO...) successfully with my custom environment function by using a feedforward netw...
12 days ago | 1 answer | 0
1
answernumerically solving an equation involving a matlab function with multiple variables
fun = @(x) blsprice(5,2,0.05,x,0.2) - 4; unknown_time = fsolve(fun,0.5)
24 days ago | 1
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I want to get 2d image from a sensor data.What matlab commands convert a dataset to images?
A = rand(100,100) imshow(A) or A = (randi(1500,100,100))-750 image(A)
30 days ago | 0
How can I name matrices generated by a for loop as Z1,Z2,Z3 ...etc.
There are a lot of contributions (one of the best is here) which show why this way of coding is bad - use an efficient way by in...
1 month ago | 1
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Problem with solve matrix
For me your code works: disp('An economic system composed of 3 sectors has the input-output matrix'); D=[0.5,0.1,0.1;0.2,0.5,0...
1 month ago | 0
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ode45 solver code for solving a system of three coupled equations does not work
Your ode appears to be stiff - therefore i recommend to use ode15s instead of ode45. Also the behaviour of your system can be se...
2 months ago | 1
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i want to read a csv file and store as rows and columns of a cell
fileID = fopen('FOM_HFA_Pavg.csv'); content = textscan(fileID, '%s','Delimiter','\t'); fclose(fileID); content = content{:}; ...
2 months ago | 0
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calculate and plot the following differential equation using ODE45solver.
y0=0.5; %intial value h=0.8; % t=[0 4]; %tspan [t,y] =ode45(@(t,y)-y+sin(t), t,y0); plot(t,y,'-o'); xlabel('time'); ylabel...
2 months ago | 0
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using Q learning agent for continuous observation space
You also are allowed to write a custom critic function: https://de.mathworks.com/help/reinforcement-learning/ref/rlqvaluerepres...
2 months ago | 0
question ..question about engine matlab
Your code works - you only need to call your function and plot the results: % Call the function and save results in W and Fa [...
2 months ago | 0
Calculate a letter from equation with letters.
You might want to do this: syms Xe Ye a1 a2 cos1 cos2 sin1 sin2 eq(1) = Xe == a2*(cos1*cos2-sin1*sin2)+a1*cos1; eq(2) = Ye ==...
2 months ago | 0
FZERO cannot continue because user-supplied function_handle ==> @(M)FindM(M,N(k),Q,wn(i)) failed with the error below.
Declare the code in findM_1P as a function and give it proper input and output arguments, to make it possible for fzero passing ...
2 months ago | 0
IMRT Beam angle optimization
You might want to read the dissertation from Mark Bangert, which includes a rich bibliography: http://archiv.ub.uni-heidelberg....
2 months ago | 0
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Error in bin2dec ?
You are not doing wrong - just read the documentation: "...If the input argument D has a value greater than the value returned ...
2 months ago | 1
Combining 3 curves into 1 average
Here is a simple example: % fantasy times times1 = 1:10 times2 = 1:2:11 % fantasy values y1 = 2 * (1:10) y2 = 4 * (1:2:1...
2 months ago | 0
A problem while using lsqnonlin
Use the same random numbers for the same results: rng('default') d = linspace(0,3); y = exp(-1.3*d) + 0.05*randn(size(d)); ...
2 months ago | 0
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Not getting six coupled ODEs solution using bvp4c in MATLAB, Please help me
I used nested functions - for 2 of the constants you did not provide values: % Call the outer function finalprogramme %% Ou...
2 months ago | 0
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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...
2 months 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...
2 months ago | 0
Please tell me how?
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(...
2 months 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)...
2 months 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); ...
2 months 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 ...
2 months 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...
2 months ago | 0
| accepted
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...
2 months 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] ...
2 months ago | 1
| accepted
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