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# Stephan

##### Last seen: Today
1.134 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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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...

8 días 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...

9 días 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...

10 días ago | 0

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Describing the motion of a composite body using system of differential equations
Solve numeric: syms y(t) z(t) Dy = diff(y,t); Dz = diff(z,t); eqns = [diff(y,t,2) == (29.4*cos(z)+4*Dz*Dz)*sin(z)/(1+3*sin(...

15 días ago | 0

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Making a Video from Images
https://de.mathworks.com/help/matlab/import_export/convert-between-image-sequences-and-video.html

16 días ago | 0

how to solve the non-linear equation
To solve for V as a function of Q: syms V Q D=1050; c=25; A=1000; B=1000; v=1.077; gamma =0.1; beta =0.1; eq = V*c*(1...

16 días ago | 0

Problem with solve function
syms s vs v1 v2 vo s R1 R2 R3 Rc1 Rc2 gm1 gm2 gm3 gmc1 gmc2 C1 C2 C3 Cc1 Cc2 k1 k2; % Nodal Analysis Equations eq1 = -gm1*vs +...

18 días ago | 0

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Solving three simultaneous equations for analytical solution
Keep it short and simple + use "*" for multiplication operations: syms k2 k1 Rk1 R BR s h a l2 l1 t1 t2 bh d eq(1) = k2==(BR*(...

18 días ago | 0

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Plotting Equation with straight line
<https://de.mathworks.com/help/matlab/ref/fplot.html |*fplot*|>

26 días ago | 0

bvp4c error
In your case bvp5c is suitable to solve your problem, without changing the timespan: solinit = bvpinit([0,1],[0,0]); sol = bvp...

28 días ago | 0

How can I make the wave in the negative part disappear?
More resolution for the values + logical indexing: t= linspace(0,6,5000); y=sin(pi*t); plot(t(y>=0),y(y>=0))

alrededor de 1 mes ago | 1

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How to convert cells within cells to double.
Due to the different lengths of all the entries you can not easily store them in a matrix, but as a column vector it will work e...

alrededor de 1 mes ago | 0

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How to solve Integer Linear program
Work through this examples: https://de.mathworks.com/help/optim/ug/intlinprog.html#bts3f9f-4

alrededor de 1 mes ago | 0

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Storing indices from a matrix
A= [ 1 2 3 -4 6 -2]' B = find(A<0) A = 1 2 3 -4 6 -2 B = 4 6

alrededor de 1 mes ago | 0

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how to do Shifting of text
A = "volatile uint8_T AtomcMduleCnt_Z_Pt = 7U;/* Atomic Module Count in Pack */" B = insertAfter(A,"uint8_T"," @") A = ...

alrededor de 1 mes ago | 0

rational curve fitting function?

alrededor de 1 mes ago | 0

Note that your link refers to R2019b. The example you are looking for in R2019a you find here: https://de.mathworks.com/help/re...

alrededor de 1 mes ago | 0

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Sort and accumulate data in a matrix
Here is an example: A = [-10 0 10 10 20 -20 30 -30 40 -50 50 -40 -10 0 0 10 20 -20 30 -30 40 -50 50 -40 40 40 40]; groups = fi...

2 meses ago | 0

How to save the 60 value in two columns as a csv file?
Use writematrix for this beginning from R2019a. For earlier releases you can use csvwrite. If x and y are of size 60x1 why not ...

2 meses ago | 0

How can I solve a nonlinear model using Newton Raphson ?
One way: result = fsolve(@fun,[1 1 1]) function F = fun(x) F(1) = x(1) + x(2).^2 + cos(x(3)) - 2; F(2) = x(1) + sin(x(2)) ...

2 meses ago | 2

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How display a log space bar figure ?
% Set y-axis to log scale set(gca, 'YScale', 'log')

2 meses ago | 0

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can anyone tell whre is the error ?
x=-2*pi:0.01:2*pi; y=exp(x); z=sqrt(exp(-x)); figure(3) p=plot(x,y,'r',x,z,'b'); p(1).LineWidth = 2; p(2).LineWidth ...

2 meses ago | 0

How to replace the empty cells in a cell array by a 4-bits string?
load('Key.mat'); Key1 = Key(:); Key1 = reshape(replace(string(char(Key1{:}))," ","0000"),size(Key,1),size(Key,2)); results...

3 meses ago | 0

How to generate a symmetric Toeplitz matrix?
>> toeplitz([-pi 0 pi]) ans = -3.1416 0 3.1416 0 -3.1416 0 3.1416 0 -3.14...

3 meses ago | 4

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"syms", "sym", and "mupad" functions cause MATLAB to freeze
R2017b had this bug, but it was fixed in update 7 and following. Try to install the latest update for your release - see Step 2:...

3 meses ago | 0

How to use VPA (variable precision arithmetic) in calculating HH band via dwt on an image?
You can not do this. dwt2 accepts only double as input and outputs double. vpa works on symbolic variables and returns a symboli...

4 meses ago | 0

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String to Categorical array
x = [zeros(1,120), ones(1,240)]; res = categorical(x, [0, 1], {'Z', 'O'});

4 meses ago | 0

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Reducing 2nd order ODE into coupled ODE. Solve using Euler Method and graph.
tspan = [0 5]; % time span to integrate y0 = [3 0]; % initial conditions %Start of Euler Method syms y(t) E = diff(y,2) + ...

4 meses ago | 0