988 total contributions since 2017

Knowledge means knowing where it is written...

Interested in:

- Optimization

- Mathematical Modelling

- Improvement of my programming skills

Answered

How to find the arc length of a trajectory?

Maybe it helps if you know the center coordinates and the radius of your circle: % your original code img = imread('image.bmp'...

How to find the arc length of a trajectory?

Maybe it helps if you know the center coordinates and the radius of your circle: % your original code img = imread('image.bmp'...

12 hours ago | 0

Answered

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 = ...

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 = ...

2 days ago | 1

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Answered

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...

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...

3 days ago | 0

Answered

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:...

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:...

3 days ago | 0

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Answered

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...

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...

4 days ago | 0

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Answered

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...

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...

4 days ago | 0

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Answered

Solving a system of equations without "syms"

doc linsolve or https://de.mathworks.com/help/matlab/ref/linsolve.html

Solving a system of equations without "syms"

doc linsolve or https://de.mathworks.com/help/matlab/ref/linsolve.html

4 days ago | 0

Answered

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...

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...

5 days ago | 0

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Answered

How to make the vessels brighter in this segmented image

I = imread('untitled.jpg'); I1 = imadjust(I,[0 0.1]); imshow(I1) results in:

How to make the vessels brighter in this segmented image

I = imread('untitled.jpg'); I1 = imadjust(I,[0 0.1]); imshow(I1) results in:

5 days ago | 0

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Answered

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) ...

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) ...

5 days ago | 1

Answered

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....

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....

5 days ago | 0

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Answered

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...

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...

5 days ago | 0

Answered

How to solve pendulum ode function?

https://de.mathworks.com/matlabcentral/answers/437764-ode45-i-get-wrong-results#answer_354579

How to solve pendulum ode function?

https://de.mathworks.com/matlabcentral/answers/437764-ode45-i-get-wrong-results#answer_354579

5 days ago | 1

| accepted

Answered

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...

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...

5 days ago | 1

| accepted

Answered

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...

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...

5 days ago | 0

Answered

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...

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...

6 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...

6 days ago | 0 answers | 0

Answered

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, ...

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, ...

6 days ago | 0

Answered

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...

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...

6 days ago | 1

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Answered

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...

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...

7 days ago | 0

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Answered

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

doc readmatrix doc contour

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

doc readmatrix doc contour

7 days ago | 0

Answered

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)

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)

7 days ago | 0

| accepted

Answered

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...

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...

7 days ago | 1

| accepted

Answered

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

Try: varInput = load('quadData.mat'); qDat = varInput.quadrotor; [n,~] = size(qDat); Xi_0 = [qDat(1,2:4)'; qDat(1,8:10)']; ...

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

Try: varInput = load('quadData.mat'); qDat = varInput.quadrotor; [n,~] = size(qDat); Xi_0 = [qDat(1,2:4)'; qDat(1,8:10)']; ...

7 days ago | 0

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Answered

Probelm in implementing Adaptive Histogram Equalization

Follow the workflow shown here: https://de.mathworks.com/help/images/ref/adapthisteq.html#bvhtu1_-1

Probelm in implementing Adaptive Histogram Equalization

Follow the workflow shown here: https://de.mathworks.com/help/images/ref/adapthisteq.html#bvhtu1_-1

7 days ago | 1

Answered

base error problem in sending email for matlab

content = 'This function works for me on gmail - try it...' e_mail(content) function e_mail(Content) recipient = {'emai...

base error problem in sending email for matlab

content = 'This function works for me on gmail - try it...' e_mail(content) function e_mail(Content) recipient = {'emai...

7 days ago | 0

Answered

The inconsistency of polyfit function

From the documentation: [p,S,mu] = polyfit(x,y,n) also returns mu, which is a two-element vector with centering and scaling val...

The inconsistency of polyfit function

From the documentation: [p,S,mu] = polyfit(x,y,n) also returns mu, which is a two-element vector with centering and scaling val...

7 days ago | 0

Answered

Make Boxes on Surface in 3D Plot

A = rand(10,5,3); A = sum(A); A = squeeze(A); surf(A,'LineWidth',2)

Make Boxes on Surface in 3D Plot

A = rand(10,5,3); A = sum(A); A = squeeze(A); surf(A,'LineWidth',2)

7 days ago | 0

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