Walter Roberson
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Content Feed
Issue with Matlab symbolic int
Use definite integrals rather than indefinite integrals. For example matlab tends to take a term that would be typically be w...
5 hours ago | 0
Error: using fmincon with integral function
%% Input syms d p G1 = 3e6 G0 = 1.25e8; V0 = 250; k0 = p/V0; V1 = 316; k1 = p/V1; %% Calculation D = [cos(k1*d) s...
5 hours ago | 0
| accepted
how to put only one item in the listbox
Are you trying to create a list that only has a single element? Such as app.ChoiseEquityListBox.Items = {'Filtered'}; app.Choi...
12 hours ago | 0
| accepted
loading images without compression
app.imageStruct.(imageName) = imread(imagePath,"png", 'BackgroundColor', [0.94 0.94 0.94]); The fact that y...
14 hours ago | 0
Splitting image channels error: Index in position 3 exceeds array bounds. Index must not exceed 1.
for k = 1 : length(fileopen) baseFileName = fileopen(k).name; fretfiles = fullfile(fileopen(k).folder, baseFileName); ...
14 hours ago | 0
| accepted
Mac and Linux users, please support me with a very simple task (VideoWriter.getProfiles())
MATLAB Version: 23.2.0.2409890 (R2023b) Update 3 MATLAB License Number: • Operating System: macOS Version: 14.0 Build: 23A344...
1 day ago | 0
| accepted
What significant test `corr` use internally?
corr() does not itself use any significance test. It returns the p values -- leaving you to make your own significance tests acc...
1 day ago | 0
Not Enough Input Arguments
I have "Num" defined in another function as a character array, But you are not passing Num into Out when you invoke Out. Ther...
1 day ago | 0
| accepted
What New Functions or Features in R2023B are of Interest?
R2023b does not have many changes of interest to me. What it does have that might be useful to me is, Find and Replace Dialog...
2 days ago | 0
error whilw downloading Copernicus Marine data via MOTU in MATLAB
motu_line = sprintf("py -m motuclient --motu https://nrt.cmems-du.eu/motu_web/Motu", ... " --service-id ", serviceId, "-TDS...
2 days ago | 0
How to calculate first and second derivative for concentration?
%first and second derivative df=diff(M1(j+1),t); You have that line before your for j loop, so at that point j is its default...
2 days ago | 0
I need help separating some horseshoe data
filename = '1147406HorseShoe.csv'; data = readmatrix(filename); Nclust = 3; [G, centers] = kmeans(data, Nclust); centers ...
2 days ago | 0
Why does MatlabR2023b frequently crashes when generating figures
-Codes can correctly generate figures (using plot function), but when I try to close the graph it stops responding Don't close ...
2 days ago | 1
How to utilizes APIs provided by robot manufactures and then control the robot
See https://www.mathworks.com/help/matlab/call-cpp-library-functions.html for C++ libraries, and see https://www.mathworks.com/h...
3 days ago | 1
VideoReader missing codec problem
Doesn't the MATLAB installation include the video codes required for the video formats VideoReader/VideoWriter supposedly suppor...
3 days ago | 1
Student licence claim duration
Depending on the country, and the payment method, and the time of day, it can be anywhere from 30 seconds to second business day...
4 days ago | 0
| accepted
How do I perform several iterations in MATLAB?
Change for K = 1 : 100 L = 1.56*(y^2)*tanh(61.58/L); end to LGuess = 60; for K = 1 : 100 L(K) = fzero(@(L) 1.56*(...
4 days ago | 0
The code runs when if I do; newton_recur(@(x) x^2,@(x) 2*x,1,10) but wont work if I leave out the @(x). is there a way to do this so that the user doesn't need to add @(x)?
In MATLAB, parameters to a function are always evaluated before being passsed to the function. There is no way in MATLAB to be a...
4 days ago | 0
| accepted
Starting parallel pool gives message about crash dump files
Some previous run or runs crashed at some point in the past. The job identifiers involved were 9 and 73 -- which were not necess...
4 days ago | 0
| accepted
run topology optimization code
You editted the code for top99neo.m which you should not have done. You need to restore the code to the original -- in particula...
4 days ago | 0
Related to creating the vectors in MATLAB
(8) (3) is 8!/(3! 5!) = 56. log2 of that is between 5 and 6. floor of that is 5. So your formula calculates N = 5, *not*...
4 days ago | 0
| accepted
Can someone help me with my code. Calculate the position (coordinates x and y) of points B C and D . Calculate the linear velocity (vx and vy) of points b c d.
Ultimately the program cannot be run because you do not define r_ab = 0.3; w_ab = 0.2; Th1_1i = 30; w_bc = -0.05; r_bc = 0...
4 days ago | 1
How can I use Excel sheet names as variables in the area (x, y) syntax?
You just go ahead and do it. For example, rng(655321) filename = 'test.xlsx'; for K = 1 : 3 sheetname = "s" + randi(6553...
4 days ago | 1
| accepted
MATLAB ignores a trisurf's FaceVertexAlphaData property
https://www.mathworks.com/help/matlab/ref/matlab.graphics.primitive.patch-properties.html#buduav0-1-FaceVertexAlphaData Note ...
4 days ago | 0
| accepted
How can I print the mean and standard deviation in the histogram plot?
You can text the information into place. Or you can put it into a title or subtitle
4 days ago | 0
I need to repeat a periodic signal
Hint: syms t F(t) = piecewise(-2 <= t & t < 0, 1, 0 <= t & t < 1, 2, 1 <= t & t < 2, 3) fplot(F, [-10 10]); ylim([-1 4]) G =...
5 days ago | 0
How can I convert handle function to a string
f=@(x) 2*x+1 syms x solve(f(x))
5 days ago | 1
How can I create a .txt files from a cellarray that is 80x1 into 80 different files with the same name with different number in the end?
for K = 1 : numel(LF) filename = "LF" + K + ".txt"; writematrix(LF{K}, filename, 'Delimiter', '\t'); end
5 days ago | 0
| accepted
format number column table/array
MATLAB does not provide any way to customize how many digits are displayed for numeric arrays, other than 2 digits ( format bank...
5 days ago | 1
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