PULL OUT A SPECIFIC WORD FROM A LONG STRING
You might want to start reading here: https://de.mathworks.com/help/matlab/matlab_prog/searching-and-replacing.html

3 months ago | 1

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How do I create a for loop to extract data from table?
No loop is needed: A = unstack(ReactionTime,'RESPONSE_TIME_ehmi','videostring') since you have invalid names for you video fil...

3 months ago | 0

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complement of an image
I = fliplr(imread('cameraman.tif')); I1 = triu((I),1); I2 = tril(imcomplement(I)); I_res = fliplr(I1+I2); imshow(I_res) B...

3 months ago | 1

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Trapz gives "Second and third argument must either be variables or a variable and a nonnegative integer specifying the number of differentiations."
syms x f_scalar = @(x) 5*x^2+3*x-4; g_scalar = @(x) -4*x^2+6*x+5; f = @(vec) arrayfun(f_scalar,vec); g = @(vec) arrayfun(g_sca...

3 months ago | 0

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Problem with input of ode113
I_1= pi^2; I_2= -2*pi^2; params.tau= 10; g= 0; V_1= -65; V_2= -65; state= [V_1;V_2]; I= [I_1;I_2]; options = odeset('ab...

3 months ago | 0

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How to define discrete variables in GA (genetic algorithm)

3 months ago | 0

Surrogate search with integer parameters
|*intcon*| was introduced to surrogateopt in R2019b. <https://de.mathworks.com/help/gads/release-notes.html>

3 months ago | 0

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Accessing value in a cell
Edited because of the comments: a = {'1,65,4,5'} b = str2num(a{:}) b(2)

3 months ago | 1

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Passing parameters in boundary value problem using BVP4C
See here: <https://de.mathworks.com/help/optim/ug/passing-extra-parameters.html |*passing extra parameters*|>. I suggest to eith...

3 months ago | 0

How to extract frames from a .mp4 video?

3 months ago | 0

Plot pixels from 2D boolean array
% your array A = randi(2,101)-1; % the result; R=255*ones(101); G=255*(-A+1); B=255*(-A+1); res = cat(3,R,G,B); ...

3 months ago | 0

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Return a value from a table
Quarter = {'Q12019'; 'Q22019'; 'Q32019'; 'Q42019'; 'Q12020'; 'Q22020'; 'Q32020'; 'Q42020'}; QuarterStartDate = ['2019-01-01'; '...

3 months ago | 1

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Inserting vertical and horizontal line in bodeplot
xline and yline should work for this purpose. Both functions were introduced with R2018b. If you use an earlier release, just de...

3 months ago | 1

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Solving EOM coupled equations using ode45
syms x(t) y(t) eq(1)=diff(y,t,2)==(3/2)*(9.81*sin(y)-diff(x,t,2)*cos(y)); eq(2)=11*diff(x,t,2)+(1/2)*cos(y)*diff(y,t,2)-(1/2...

3 months ago | 1

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Array indices must be positive integers or logical values. Error in (line 8) mr(t)=mi-((mi-mf)*(t./tb));
I doubt you want t to have only one point. Also no for loop is needed: mi=2290000; mf=130000; tb=165; t=linspace(6.5,165...

3 months ago | 1

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could anyone help me how to combine data in two columns
Res = [A B]

3 months ago | 0

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Not able to use ode45 to solve and plot solution to vdp equation
You are missing some things. Looks like a mix of numeric and symbolic calculations, which won't work. But tou have luck - exactl...

3 months ago | 0

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How to divide column vector elements in unequal parts against a condition?
Due to different lengths of your daily data you should use a cell array: A = readmatrix('New Text Document.txt'); k_min = mi...

3 months ago | 1

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how to solve inequality in matlab R2016a
In 2019b this works by using an assumption: syms x real eqn = (x-1)*(x-2)*(x-3)*(x-4)> 0; S = solve(eqn, x) % Test solutio...

3 months ago | 0

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Tspan is not strictly increasing.
Since ode45 uses an automated stepwide control just define the start and the end of your tspan this way: tspan = [0 10]; This ...

3 months ago | 0

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Subplot in ODE45
d = [0.20 0.30 0.50]; for ii = 1:numel(d) sol(ii)=ode45(@(t,C)b2(t,C,d(ii)),[0 2],[130 10 5]); t{:,ii}=sol(ii).x'; ...

3 months ago | 1

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How to print greek letters like 'ยต' in fprintf to file handle?
fileID = fopen('testFile.txt','w') fprintf(fileID,['16.0', char(181), 'm']); fclose(fileID)

3 months ago | 0

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Differential Equation Problem using ode45
[W,Fa] = PBR_Isothermal; % plot results subplot(3,2,1) plot(W,Fa(:,1)) subplot(3,2,2) plot(W,Fa(:,2)) subplot(3,2,3) pl...

3 months ago | 1

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problem in optimization by MATLAB using genetic algorithm
Change myFitness.m to: function y = myFitness(x) s = x(1) z = x(3) x = x(2) y = ...YOUR EQUATION HERE end also change thi...

3 months ago | 0

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optimixation by genetic algorithm using MATLAB
Get rid of the square brackets - Matlab will interpret this as one input argument of a vectorized function. Therefore it throws ...

3 months ago | 0

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Plotting points that pass through y for x,y,z coordinates
Data=[0.345 0.343 0.341 0.339 0.337 %sample x data -0.005 -0.002 -0.00069 0.0015 0.0034 %sample y data 0.284 0....

3 months ago | 1

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Time-dependent parameter for ODE system
use interp1 to achieve this - an example of how to do this is here.

3 months ago | 0

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plot a mathmatical function
https://de.mathworks.com/help/matlab/ref/fplot.html

3 months ago | 0

Intelligent symbolic variable substitution
syms f(x) z(x) fun = f == x^2 + 8*x + 16; % equals (x+4)^2 transform = z == (x+4)^2; subs(fun, rhs(fun), lhs(transform))...

3 months ago | 0