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 ...

28 days ago | 1

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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 = ...

28 days ago | 0

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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...

28 days ago | 0

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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)

28 days ago | 0

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...

29 days ago | 1

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...

29 days ago | 0

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...

29 days ago | 1

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

30 days ago | 0

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...

30 days ago | 0

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.

30 days ago | 0

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 ...

30 days ago | 1

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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^...

1 month ago | 1

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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...

1 month ago | 1

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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 ...

1 month ago | 0

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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 tÅ‚oka p1=0.5...

1 month ago | 0

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Integration using trapz method
1 missing bracket and you missed to define dx: d = 30; E0=8.85e-12; c=.1; dx = 0.1; a = 0; b = 1; x = a:dx:b; N = lengt...

1 month ago | 0

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Meshgrid fo variables in complex equation
You might want to try fimplicit3: syms f(x,y,z) f(x, y, z)=2*x+3*y+4*z==0 fimplicit3(f) or an even more complex example: f(...

1 month ago | 1

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Define vector v in the code
v=[2,-3,-5,6] result = prod(v(v>0))

1 month ago | 0

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How to split an cell array of two numbers into two columns
YouWant = [m5{:}]'

1 month ago | 0

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How to calculate matrix M*T=T
syms T2 T3 M = [1., 0, 0, 0;... 0.5, 0, 0.5, 0;... 0, 0.5, 0, 0.5;... 0 0 0 1.] T = [500; T2; T3; 300] B =...

1 month ago | 0

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how would i change an undirected network into a directed network on matlab?
here is a small example: A = [0 0 1; 0 0 1; 1 1 0] ug = graph(A) B = zeros(size(A,1)) B = B + triu(A) dg = digraph(B) ...

1 month ago | 1

Simplify a symbolic expression
syms s T=21.0325 L=3.5890 X=(0.6*T)*((s+(1/L))^2)/s vpa(expand(X),10)

1 month ago | 0

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which optimization method should I use?
Following your statements surrogateopt appears to be the correct choice.

2 months ago | 0

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Invalid array indexing. column 19.help
epsilon(i)(xi2(i)((1-epsilon(i)) is not allowed in Matlab, do you mean?: epsilon(i)*(xi2(i)*((1-epsilon(i))

2 months ago | 1

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Matlab Code (Reinforcement Learning in Finance by Alex Roumi, MathWorks)
The code has never been published. Usually the code used in webinars is published at file exchange, but this was a presentation ...

2 months ago | 0

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Error using horzcat:: Dimensions of array being concentenated are not consistent
There are 2 times the same values at different indices. To get only the first occourence: S=[.2046e17 .1381e17 .9249e17;.1679e1...

2 months ago | 0

How do i create a "Cut" at origin?
A = 5; M = 0.8; w = 1.2; fi = 30; t2 = 20; firad = fi*pi/180; t = linspace(0,t2,1000); y = M + A*sin(w.*t + firad); ...

2 months ago | 0

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Creating matrix with diag command
This is how a normal Matlab user would so this z = diag(1:10) z = 1 0 0 0 0 0 0 0 0 ...

2 months ago | 0

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not enough input data
Note that i used the same function for step2 like step1 to make it work - replace step2 with the correct function. Also i assume...

2 months ago | 0

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