Walter Roberson
41,685 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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Matrix Randomize with order
There cannot be any solution to this problem. Consider that you have 21 columns. Each "line" (including columns) can have a ma...
1 hour ago | 0
distance between randomly selected nodes
xt = [CC.xd]; yt = [CC.yd]; distances = squareform( pdist([xt(:), yt(:)]) );
2 hours ago | 0
Functions: converting Fahrenheit to Celsius
When you define a function inside a script, the function cannot have the same name as the script .m file.
2 hours ago | 1
Plot different functions in the same graph?
plot first function hold on plot second function h3 = plot third function for t = 1 : whatever calculate new X and Y to...
2 hours ago | 0
Matrix dimensions must agree error when converting from jg2 to tiff
fileparts returns character vectors, not string objects. baseFileNameYeet is a character vector. You are trying to do arithmetic...
2 hours ago | 0
How to integrate within a loop with an interpolating function?
You have x=(-4:0.05:4); y=(-4:0.05:4); [X,Y]=meshgrid(x,y); those put specific numeric arrays into X and Y. Z1=3*(1-X).^2.*...
2 hours ago | 0
Plot won't show up for plotting error for SOR method
err = zeros(1,m); for w = 1 : m x = sor1_fn(A,b,w,X0,n_iter); err(w) = norm(x_true - x); end plot(1:m, err);
20 hours ago | 0
Importing data from a file in a specific way
fileID = fopen(file, 'r'); formatSPec = '%f %f %f'; sizeA = [3 Inf]; %notice not [Inf 3] A = fscanf(fileID, formatSpec, siz...
20 hours ago | 0
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Not enough memory to open .nii file
.nii files are binary files. You should not be trying to edit them in MATLAB. You should use https://www.mathworks.com/help/imag...
22 hours ago | 0
Extract certain rows of matrix if they have a certain number
mask = ismember(M(:,4), 17:21); afternoon_M = M(mask,:); There are other ways to write the test, such as mask = M(:,4) >= 17...
23 hours ago | 1
Unable to perform assignment because the left and right sides have a different number of elements, Fisheriris
gscatter() returns a number of handles equal to the number of groups it detects. Since you appear to have 8 groups, it will prob...
24 hours ago | 0
How to write binary numbers in a txt file?
The result of dec2bin is a char array. A char array is a single parameter as far as %s is concerned. If you are using R2016b or...
1 day ago | 0
How to define a variable form a value in for loop?
This is really not recommended If you insist on doing this not-recommended thing
1 day ago | 0
Can I specify C matrix with tf2ss?
You cannot specify the C matrix in a tf2ss() call. It always calculates the C matrix based upon the numerator and denominator. L...
1 day ago | 1
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How to plot function part by part?
duration = 10; Fs = 20; %samples per second secs_per_plot = 2; data = randi([-5 5], 1, duration*Fs); %example data fo...
1 day ago | 0
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How does the operation take place for, b (2:6, 2:6) = b(1:5, 2:6) + b(3:7, 2:6) + b(2:6, 1:5) + b(2:6, 3:7); , row-wise manner ?
The first code extracts all the various subsets of the b array before doing any assignments. For example b(3,4) is part of each ...
1 day ago | 1
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Undefined function 'initializeParameters' for input arguments of type 'double'. This is what i get when i run. Please help
https://www.mathworks.com/matlabcentral/fileexchange/69238-hyperspectral-image-classification You need to install that. If you ...
1 day ago | 0
Index in position 2 exceeds array bounds (must not exceed 3).
Because g includes 4, at some point you are going to try to access l(1,4) . However you only initialize l to (3,3) so l(4,:) and...
1 day ago | 0
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how to append a mat file
You cannot do that with save() Have a look at https://www.mathworks.com/help/matlab/ref/matfile.html
1 day ago | 0
Passing values to Bash script
Example: cmd = sprintf('alpha=%d beta=%d ls | head -$beta | tail -$alpha', alpha, beta); system(cmd)
1 day ago | 0
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UiTable HTML not working
uitable for app designer is not based upon the same underlying technology, and does not support html for coloring. I do not kn...
1 day ago | 0
Array indices must be positive integers or logical values error
You initialize nT to 0. You access wk(nT) but nT is still 0. You need to move the increments of nT to before you use nT as ind...
2 days ago | 0
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Finding value of x using integral
The right hand side is a constant. Compute it first. Suppose I refer to that as RHS. Then you can fsolve(@(Xa) integral(@(XA...
2 days ago | 0
How to convert 1x21 array to table
lambda_table = table(labmda(:), 'VariableNames', {'lambda'});;
2 days ago | 0
How to calculate monthly data from daily rainfall data in a time-seris 3-dimensional matrix?
mat2cell() to break the 17 x 22 x 332 up into cell arrays 17 x 22 x number_of_days_in_month . Then you can cellfun(@(M) sum(M,3)...
2 days ago | 0
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fsolve problem
It is not possible to set bounds for fsolve() . You can set the FunValCheck option for fsolve() to tell it to check each iterati...
2 days ago | 0
Can I divide a linear array by a number which larger than its size ?
Next20 = @(V) ceil(length(V)/20) * 20; Interp20 = @(V) interp1(V, linspace(1, length(V), Next20(V))); Split20 = @(V) mat2cell(...
2 days ago | 0
Sending <ESC> T over Serial port to Scale
fprintf(s, '%cT', 27) you might also need to send a terminator
3 days ago | 0
MATLAB code that execute exp function without using the exp inbuilt function
See https://www.mathworks.com/help/fixedpoint/ref/cordiccexp.html
4 days ago | 0
Index exceeds the number of array elements (2) Error
Your assignment to h(i) after the if expects vt(i) to have been assigned to. However, if the if condition was false, then the as...
5 days ago | 0