Community Profile

# Stephan

991 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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R2018a contained wlan example code, but none of it is in R2019b. What happened to all the wlan example code?
There is a bunch of examples here: <https://de.mathworks.com/help/wlan/examples.html>

22 hours ago | 0

How to convert a matrix to a vector
M1=reshape(M.',[],1)

1 day ago | 0

I don't know why ODE45 function does not count time. Runs forever.
Your code repeats calculations on constants that should be done only once for performance - but more important ist that your ode...

3 days ago | 3

How to find the arc length of a trajectory?
Maybe it helps if you know the center coordinates and the radius of your circle -after that you can calculate the angles and use...

3 days ago | 0

Conversion of 2000x3 decimal matrix .txt file into binary 2000x3 .txt file
This should work: A = readmatrix('test_input_xyz.txt'); [sz1, sz2] = size(A); A = reshape(A,[],1); B = sdec2bin(A,12); B = ...

6 days ago | 1

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Error in simulation using ODE15s (probably with vertcat)
function template %set the parameters p = set_parameters; %set the initial conditions input.Conc= [100 0 0];%target viru...

6 days ago | 0

how to change size of a string?
a = 'K10' b = string(a) whos

7 days ago | 0

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Linear regression - extracting info using matrix algebra
add a column of ones to your matrix DATA in pos. 4. isolate income as a column vector and remove this column from DATA then use:...

7 days ago | 0

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how can write PSO constraints
Use the lower and upper bounds input argument, like shown in the documentation: <https://de.mathworks.com/help/gads/particles...

7 days ago | 0

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Error in ODE 45: MYODE must return a column vector.
To solve this error make sure that dy is column vector. dy = [du; dv] could already solve the problem - but only if th...

8 days ago | 0

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Solving a system of equations without "syms"
doc linsolve or https://de.mathworks.com/help/matlab/ref/linsolve.html

8 days ago | 0

How to covert unit of Voltage(V) to acceleration(m/s^2) and in speed (m/s)
https://wikimedia.org/api/rest_v1/media/math/render/svg/438ac92993d4032c8660665fcb017cbe76c4a113 The last term on the right sid...

8 days ago | 0

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How to make the vessels brighter in this segmented image

8 days ago | 0

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How this is possible? "atan(x) function problem"
What is the problem? https://en.wikipedia.org/wiki/Inverse_trigonometric_functions#arctan a = 1/0 a = Inf atan(a) ...

8 days ago | 1

converting Matlab plot example
trop =[0.2571;-0.9444;-1.3218;0.9248;0.0000;-0.0549;0.9111;0.5946;0.3502;1.2503;0.9298;0.2398;-0.6904;-0.6516;1.1921;-1.6118;-0....

9 days ago | 0

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how to measure angle and flame speed from Picture ..
Usually i would not open a new answer - but this question is weird, because i can not comment it for some technical reason. Howe...

9 days ago | 0

How to solve pendulum ode function?

9 days ago | 1

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Why is my fimplicit plot empty?
The warning means, that Matlab did not find an analytical solution - solve numeric: syms x(t) Dxt(t) ode = diff(x,t,2) + ((4.2...

9 days ago | 1

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DOUBLE cannot convert the input expression into a double array?
clc; clear; anglout = rad2deg(pi); true_value = cos(pi/3); h = pi/3-pi/4; n = 6; syms f(x) op(x) f(x) = cos(x); sol = z...

9 days ago | 0

Matrix indexing in a function
It is a good idea to work with polyshape objects in this case: % Find intersected circles P = [0 0 1; 1 1.5 0.75; 2 1 0.5]; f...

9 days ago | 0

Question

Can not comment / edit one single question in Answers
I tried to comment on the following question, to come up with an improved version of the code: https://de.mathworks.com/matlabc...

9 days ago | 0 answers | 0

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Read time and numerical data from txt file and plot in matlab.
If you use R2019a or later, maybe this is interesting for you: https://de.mathworks.com/help/matlab/ref/readvars.html also, ...

9 days ago | 0

creating a row vector
A(1:5) = 5

9 days ago | 0

how to measure angle and flame speed from Picture ..
I used this documentation example to build this code: % find lines I = imread("5t.JPG"); I1 = rgb2gray(I); I1 = imbinarize(I...

10 days ago | 1

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Optimization of model parameters
Since you have measured values and you have an equation you should use lsqcurvefit to estimate the parameters. You find examples...

10 days ago | 0

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how do I transfer my excel input data into a contour graph on Matlab

10 days ago | 0

Error: Array indices must be positive integers or logical values.
the expression kw((N+1)*dr^2) is the problem. I suspect a missing * or / - for example: kw*((N+1)*dr^2)

11 days ago | 0

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Sort does not work
Why? for me the indices are correct sorted. The smallest value is found at pos. 3 and the biggest value is found in pos. 4. What...

11 days ago | 1

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Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters.