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Stephan


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1.443 total contributions since 2017

Knowledge means knowing where it is written...

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Answered
How to get certain matrix columns.
A = [1 2 3 4 5 6 7 8 9 10 11 12; 13 14 15 16 17 18 19 20 21 22 23 24] A1 = reshape(A',2,[]) b = A1(:,1:3:end) b = b(:)'

alrededor de 8 horas ago | 1

| accepted

Answered
The end operator must be used within an array index expression.
See the original question - i fixed the error. frame = read(v,[600:600:end]); will not work in this case.

alrededor de 9 horas ago | 1

| accepted

Answered
how to remove trailing zeros after rounding a matrix?
format short A = 1.23 format shortG A = 1.23

alrededor de 9 horas ago | 0

Answered
How to extract a frame every 10 s from the video ?
https://de.mathworks.com/help/matlab/ref/videoreader.read.html#busxibt-2 In your case the interval to take the first frame afte...

alrededor de 9 horas ago | 1

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Answered
matrix multiple rows with the same value
repmat([20:145:600],2,1)

alrededor de 10 horas ago | 1

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Answered
not enough input argument error
timespan=[0 15]; y0 = [0 1 0 1 0 1]; [t,y] = ode45(@repressilator,timespan,y0); figure() plot(t,y) xlabel('Time') ylabel(...

alrededor de 11 horas ago | 0

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Answered
Help: How to add a label (cell 1 x 20) to each bar (total 20 bars) in a bar plot where the bar plot has a 1x 2 dimension?
Try: labels=reshape({'A', 'B', 'C', 'D','E', 'F', 'G', 'D','A', 'B', 'C', 'D','A', 'B',... 'C', 'D','A', 'B', 'C', 'D'}',1...

alrededor de 11 horas ago | 0

Answered
How to calculate the center of white part?
Look at the regionprops examples.

alrededor de 14 horas ago | 1

Answered
Linear Interpolation code and plotting
interp1([1 6],[log(1) log(6)], 2)

1 día ago | 0

Answered
Error of sym>convertChar
syms a b c x f = str2sym('a*x^2 + b*x + c') subs(f,x,5) subs(f,[x a b c],[5 1 2 3])

1 día ago | 1

Answered
Optimising parameters in ODE with fminsearch or fmincon and ode15s
I had to make some guesses, check how to adapt the code: a = fminsearch(@myObj,[300 0]); function obj = myObj(a) % only one...

1 día ago | 0

Answered
How to solve a cubic equation using Genetic Algorithms?
start here: https://de.mathworks.com/help/gads/ga.html?searchHighlight=ga&s_tid=srchtitle#mw_a07ddf7d-face-4243-a656-f1528b592d...

1 día ago | 0

Answered
Solving an ODE second order
change to the initial conditions as you need: % symbolic variables syms a b y(x) % Define derivatives Dyx = diff(y,x,1) D2y...

1 día ago | 0

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Answered
tan(x) graph
I guess you know that your picture is not a tan function... fplot(@tan,[0 7],'LineWidth',2)

1 día ago | 0

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Answered
Detection of parts of circles (shape detection)
I dont think that this is correct: "...sometimes the lense is fully in the picture and sometimes not, which makes circle detecti...

1 día ago | 0

Answered
Solving equation with symbolic vector variable
use the dot-notation a = [1 2 3 4]; x = sym('x', [1 4]); eqn = a + 4.*x == x; sol_x = vpasolve(eqn, x) sol_x.x1 sol_x.x2 ...

2 días ago | 1

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Answered
Splitting time into hours : minutes : seconds from a fractional value.
I guess 15.76 means hours in decimal numbers: [h,m,s] = hms(hours(15.76)) d = duration(h,m,s) gives: h = 15 m = ...

3 días ago | 0

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Answered
Why linsolve cannot solve this very simple equation?
To solve this, the rank should be 3. Row 1 and 3 are not linear independent. A = [4,2,2; 5,1,3; 6,0,4] B = [60; 70; 80]; r1...

3 días ago | 0

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Answered
Why find cannot handle this very simple task?
You are dealing with doubles, they are not precisly 0.077 - use round: X = -0.1:.001:.25; find(round(X,3) == .077)

3 días ago | 0

Answered
Storing datetime double in a table
%%%Set this to desired sheet sheet = 'Test'; %Sets Date time format for when table is read opts = detectImportOptions("Weat...

3 días ago | 1

Answered
step respone, impulse response
s=tf('s'); kb=52; k1=156; k2=53; G1=10/(s+0.01); G2=G1/(1+kb*G1); G3=G2*k2*k1; G4=G3/(G3+1); subplot(2,1,1) impulse(G...

4 días ago | 0

Answered
How can I do such a "countifs"(excel) process in Matlab?
You do it by logical indexing: A = randi(10,1,15) CountIf = numel(A(A>5)) gives: A = 9 7 4 10 1 5...

4 días ago | 1

Answered
Dijkstra's Algorithm
You could make life easier using Matlab inbuilt graphs functions. One example is <https://de.mathworks.com/help/matlab/ref/graph...

4 días ago | 0

Answered
How to find the sum of duration if the consecutive row elements are the same?
Save the durations you calculated using *|diff|* in an additional column so that the durations are correct for every row in your...

4 días ago | 0

Answered
How can i sum up 56-year daily precipitation data from APHRODITE (netcdf file) into monthly?
If you organize your data in a timetable you can use retime to sum up monthly.

4 días ago | 0

Answered
Generate new column from cumulating another
A = (1:4)' A(:,2) = cumsum(A) gives: A = 1 2 3 4 A = 1 1 2 3 3 ...

4 días ago | 1

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Answered
mathematical expression from string input
https://de.mathworks.com/help/symbolic/str2sym.html >> fun = str2sym("(sin(sqrt(x)+a) * e^sqrt(x)) / sqrt(x)") fun = (e^...

4 días ago | 1

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Answered
Solve formal equation and get the solution with these variables
syms i1 i2 ib v1 v2 hie hre hfe hoe hfb eqns(1) = i1==-ib-hfe*ib+(v1-v2)*hoe; eqns(2) = i2==hfe*ib+(v2-v1)*hoe %ib==-v1/hie...

4 días ago | 0

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Answered
Importing a table with unknown number of rows
I dont think it is needed to specify this, using readtable function. I never used this option to import a .csv-file as table in ...

5 días ago | 0

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Answered
Problem with solution seemingly simple linear system of equations [0x1 sym]
rewriting the system to matrix shows that this system has no solution, due to inconsistence: d=32; %mm - Srednica tłoka p1=0.5...

5 días ago | 0

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