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Walter Roberson


Last seen: Today
51.235 total contributions since 2011

I do not do free private consulting. If you want to bring my attention to something, send a link to the MATLAB Answers location.

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Answered
From plot to video
See getframe() https://www.mathworks.com/help/matlab/ref/getframe.html and videowriter() https://www.mathworks.com/help/matlab/r...

etwa 14 Stunden ago | 0

Answered
Some Errors I couldn't fix (gui)
You can go in and edit the callbacks using GUIDE... but the easier solution is to add these to the bottom of the code: function...

etwa 14 Stunden ago | 0

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Answered
how to integrate the function?
syms theta t__c t_prime x v__x y omega t part1 = 1/(1+2*t_prime/t__c) part2 = exp(-2*((x-v__x*t_prime).^2 + y.^2)/((1+2*t_prim...

etwa 14 Stunden ago | 0

Answered
How do I stop the calculation in a for loop?
The division by 50 is just to make the output shorter for this demonstration. format long g n = 4; v = rand(n,2) / 50; for f...

etwa 14 Stunden ago | 0

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Answered
how can I buy license Matlab and Simulink From Viet Nam?
You cannot choose the version for Student licenses; you can only purchase the latest version. In Viet Nam, Mathworks operates t...

etwa 15 Stunden ago | 0

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Answered
How to gradually plot two simultaneous graphs in MATLAB gui?
a = 0:0.01:1; x = sin(2*pi*3*a); y = cos(2*pi*a); fig1 = figure(1); ax1 = axes(fig1); fig2 = figure(2); ax2 = axes(fig2)...

etwa 15 Stunden ago | 0

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Answered
Merge Variables in Table
names = YourTable.Properties.VariableNames; initials = extractBefore(names, 2); [G, id] = findgroups(initials); newTable = ta...

etwa 15 Stunden ago | 1

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Answered
Double sumation of mathmatical equation
What is the ? It looks like a function or integration or something like that. I recommend that you reverse the order of summat...

etwa 15 Stunden ago | 0

Answered
Confusion about specifiers and output
When I open the cell, it shows the output with 4 decimal places That does not mean that the decimal places are not stored -- it...

etwa 15 Stunden ago | 0

Answered
how to plot a graph gradually?
a = 0:0.1:10; x = sin(2*pi*3*a); for i = 1:length(a) plot(a(1:i),x(1:i)) pause(1) end However I recommend that you...

etwa 16 Stunden ago | 0

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Answered
Does Macbook Air M1 is well-oprimized MATLAB?
The reports I am seeing is that it is already decently fast even in emulation, and is expected to get faster as more of it goes ...

etwa 17 Stunden ago | 1

Answered
Iterating Through Multiple Structures in One Structure
A = struct(); for K = 1 : 4 ts = struct('pqr', randi(9, 1, 3), 'stu', randi(9, 1, 3)) n = char(randi(0+['a', 'z'], 1, 5...

etwa 18 Stunden ago | 0

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Answered
Create a vector in 15-minute intervals (from 0 am to 24 pm)
Sure, you can xticks() with datetime objects if you have a datetime ruler. The problem is being able to read it. Every 15 minu...

etwa 20 Stunden ago | 0

Answered
generate square wave using piecewise function and plot it
PulseLength = 50; CycleLength = 1000; ReduceCycle = @(x) x - CycleLength*floor(x/CycleLength) syms t y(t) = piecewise( Reduc...

etwa 21 Stunden ago | 0

Answered
What is the Best Way to Deal with an Empty Line Object?
i1 = x<=3; i2 = x > 100; i3 = x >= 7; plot(x(i1),y(i1),'r',x(i2),y(i2),'b',x(i3),y(i3),'g'); hold on hlines = plot(nan,nan...

etwa 21 Stunden ago | 0

Answered
use gpu for image processing
generateParams(image, param_one); % saves results in image1_result.mat % create corresponding database for the ...

etwa 22 Stunden ago | 0

Answered
Replace a variable in differential equation with 0
syms T(t) SigmaT(t) BetaV(t) Lemda To ode = diff(T,t) == ((Lemda-((SigmaT(t)).*T))-BetaV(t).*T(t)) cond = T(0) == To; zerofun...

etwa 23 Stunden ago | 0

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Answered
Replacing Variable in an ODE
syms T(t) Lemda Sigma To ode = diff(T,t) == (Lemda-(Sigma.*T)); cond = T(0) == To; Solution = dsolve(ode, cond)

etwa 23 Stunden ago | 0

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Answered
0000000000000000000000000000
G = tf([1], [1, 4, 3, 3.553e-15, 1, 1, 0]) N = cellfun(@discardsmall, G.Numer, 'uniform', 0); D = cellfun(@discardsmall, G.Den...

etwa 24 Stunden ago | 0

Answered
Sort table with a specific order
[found, idx] = ismember(T.Site, [3,4,5,6,7,1,8]); if any(~found) error('Site not on approved list, first at row %d', find(~...

etwa 24 Stunden ago | 0

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Answered
how can i covert C# code to matlab code ?
You do not convert that C# to MATLAB. It involves a number of uses of what appears to be a class or package, ETVenus that is und...

etwa 24 Stunden ago | 0

Answered
How can I check the needed inputs in an function handle?
eq1 = matlabFunction(dgl1); Your pdgl are symbolic expressions that might involve just x, just y, both x and y, or neither....

ein Tag ago | 1

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Answered
Unable to resolve the name phased.internal
internal is not an attribute . internal is just part of the name. MATLAB uses internal as part of names to indicate that the fun...

ein Tag ago | 1

Answered
How to fix PATTERN must be a string or cell array of strings error?
pos = curx>=x; pos = strfind(pos,1); In MATLAB, it is permitted by undocumented to pass in numeric or logical array...

ein Tag ago | 0

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Answered
Checking every norm of a row in a matrix with all other rows.
dists = pdist(p); The default is euclidean norm. The result would be n x n

ein Tag ago | 0

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Answered
How to set which part of the code to comment using a variable?
If practical, vectorize the Algorithm* routines, and combine them into one routine that also takes the flags. DataIn = randn(1e...

ein Tag ago | 0

Answered
How to do OR operation of two images (DFT and Binary)?
m=imshow(uint8(abs(Output)/60)) should be replaced with m = uint8(abs(Output)/60); imshow(m) and OR1=bitor(g, m); s...

ein Tag ago | 0

Answered
Problem related complex number equation in Matlab
format long g C = 3e8; t = 1; f = [2e+8, 2.96e+8]; mu_prime = [4.76, 4.75]; mu_dprime = [7.79e-01, 6.81e-01]; eta_prime ...

ein Tag ago | 0

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Answered
how to make an array of characters of variable length?
n=5; 'a':char('a'+n-1)

ein Tag ago | 1

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Answered
Can someone check my code and rectify me, getting constant output but needs changing.
[t,X]=ode23s(@(t,X) new_try_func(t,X,v,cellden,mb,u,udeathf,gal,urd,glc,asn,amm,glu,lac,gln,asp,qAmm,qUrd,qGln,qGlc,qGal,qLa...

2 Tage ago | 0

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