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Walter Roberson


Last seen: Today
50 600 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
Loop structure for fixed point.
and the correct answer when I calculated manually is 2.7424 No it is not. The correct answer is 2.71934053986603 format long ...

37 minuter ago | 0

Answered
fimplicit increasing number of points
fp = fimplicit(@(x,y) x.^2 + 2*y.^2 - 1); %Example Points1 = [fp.XData;fp.YData]; axis equal title('mesh default = 151') f...

ungefär en timme ago | 0

| accepted

Answered
Error: Invalid expression log equation
syms t a eqns =-a*log((3*t/4)*(3-t^2)/(2-t))-(1-a)*log((1/t^2)*((3-2*t)/(2-t)))+a*((1-t)^2)*(3-t)/((2-t)*(3-t^2)-(1-a)*(1+t)...

ungefär en timme ago | 0

Answered
courbe de suivie des pixels dans les images
for n=1:25 k=dicomread(fullfile(rep, list(n).name)); end; Why do you read all of them but immediately throw all of them away ...

ungefär 2 timmar ago | 0

Answered
Need Help with GUI errors
"clear all" is not appropriate inside any program and can cause odd problems. You should be opening the arduino in the OpenF...

ungefär 5 timmar ago | 0

Answered
Why do I keep obtaining complex matrices if I have only real values?
When you use root() or solve() of a degree 4 polynomial, some of the terms of the computation inherently involve imaginary compo...

ungefär 8 timmar ago | 0

Answered
~isequal and ~= not working
if ~isequal(transpose(ValueOfd), m) disp("A is not diagonalizable") else disp("A is diagonalizable") end

ungefär 9 timmar ago | 0

Answered
custom axis at the imshow
Your tick marks are not linear in x or in y. On my monitor, the distance between the first -15 and 0 is close to 1 cm more than ...

ungefär 13 timmar ago | 0

Answered
Need help with a for loop implementation for the below code
map(:,:,itrial) = sparse(ceil(eye.y(~blink)/binsz)+y0,ceil(eye.x(~blink)/binsz)+x0,1,sz(1),sz(2)); The right hand side appears ...

ungefär 14 timmar ago | 0

Answered
Need help with Reed-Solomon Coding
n = 255; img = imread('pout.tif'); binary = img > 102; resized = imresize(binary,[291 247]); [row k] = size(resized); g...

ungefär 23 timmar ago | 0

| accepted

Answered
Check for missing argument or incorrect argument data type in call to function 'sinc'.
The code works for me. You might have a sinc.m of your own that is interfering. Check which -all sinc You might see /Applicat...

ungefär 23 timmar ago | 0

Answered
How to use "ga" (genetic algorithm) for curve fitting
cost_wrapper = @(x) Cost(x(1),x(2),x(3),x(4),x(5),x(6)); coef = ga(cost_wrapper, 6)

ungefär 23 timmar ago | 0

| accepted

Answered
Please help! Am trying to find c(n)
k is a symbolic variable. You can never use a symbolic variable as part of an index, the way you do in c(n-k) You are confusin...

en dag ago | 0

Answered
Plotting a logical function if a value is greater than 0
torvals = linspace(0,6); ntor = length(torvals); C = categorical(nan(ntor,1), (1:6),{'AB', 'BC', 'CA', 'AG', 'BG', 'CG'}, 'o...

en dag ago | 0

Answered
Tic-tac-toe winner check
xmask = TTCboard == 1; if all(xmask,1) || all(xmask,2) || all(diag(xmask)) || TEST_FOR_THE_OTHER_DIAGONAL x wins end

en dag ago | 0

| accepted

Answered
help request in EEMD (Ensemble Empirical Mode Decomposition)
The eemd function you supply can only return modes, but your sample code asks for residual as well, so you must not be using tha...

en dag ago | 0

| accepted

Answered
How to call a .txt file containing dates in format "01-JAN-2019" and time against three other independent variables to MATLAB?
filename = 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/584765/data.txt'; t = readtable(filename, 'Format'...

en dag ago | 1

| accepted

Answered
How to find values for corresponding elements
wanted_output = nan(length(time_vector),1); mask = islocalmax(Q); wanted_output(mask) = Q(mask);

en dag ago | 1

| accepted

Answered
How to open Matlab with specific scripts in my editor?
See https://www.mathworks.com/matlabcentral/answers/344124-restore-open-files-in-editor-from-previous-sessions https://www.mat...

en dag ago | 0

Answered
How to use solve with a equation with limit
syms b1 c1 s a = 1; b = 7.598; c = 6.784; kp = limit(20.185/(a*s^2+b*b1*s+c),s,0) Notice this is constant, not dependent on...

en dag ago | 0

| accepted

Answered
How to close graph help popup from command line?
Perhaps https://www.mathworks.com/help/matlab/ref/disabledefaultinteractivity.html See also https://www.mathworks.com/help/mat...

en dag ago | 0

Answered
Finding a variable between a a lot of m files
In the main MATLAB command window, look on the HOME tab, in the ribbon, 5th entry is "Find files". Click on there and you will b...

2 dagar ago | 0

| accepted

Answered
matlabFunction: Index exceeds the number of array elements for Matlab R2021a
matlabFunction has a bug in writing any function using piecewise to a file in expression that is complicated enough that the fun...

2 dagar ago | 0

| accepted

Answered
How to define a binary decision variable as upper and lower bond in an optimization function?
https://www.mathworks.com/help/gads/particle-swarm-optimization-algorithm.html You cannot use integer constraints with the Mat...

2 dagar ago | 1

Answered
Problem with matlabFunction throwing error in latest MATLAB version
There is a bug in matlabFunction in R2021a, in a section of code that did not exist at all before (and had no analog at all befo...

2 dagar ago | 0

| accepted

Answered
MATLAB write a function that generates n x n matrix WITHOUT built in functions.
Your S is symmetric. However, your code uses the undefined variable A B = A' + A; B(1:n+1:end)=diag(A); %This part is suppos...

2 dagar ago | 1

Answered
fprintf returns blank square for value of 1?
You are trying to use a %s (string) format to display floating point data. Use a %f or %g format instead. DRAT = [72 105] fpri...

3 dagar ago | 0

| accepted

Answered
Factorial(1000) as number
vpa(factorial(sym(1000)))

3 dagar ago | 0

| accepted

Answered
how to make nxn matrix
n = 7 d = ones(1,n-2)/2; M = zeros(n,n) + diag([0,d],+1) + diag([d,0],-1); M(1) = 1; M(end) = 1; M

3 dagar ago | 1

| accepted

Answered
Need to find the smallest [n] such that the sum for a harmonic series is greater than some value X.
n = 25000; %max number of rows that will print S = 0; %initial starting value of sum for i...

3 dagar ago | 1

| accepted

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