Community Profile # Walter Roberson

Last seen: Today Active 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. I am currently caught up to T0099000; if you are waiting on a reply from me for an older issue, please send me a reminder.

Programming Languages:
C++, C, MATLAB, Shell, Perl, Fortran
Spoken Languages:
English

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Surface plot error for Z must be a matrix, not a scalar or vector
careful, x is (eventually) going to be 3d, and the way you use size is wrong for 3d. I have seen cases where z was returned a...

alrededor de 2 horas ago | 0

(HOW) I need the code run again if the ( else condition return ) till give me value
do_again = true; while do_again do_again = false; for i= 1:7 for j=1:7 if (i~=j) if % coditi...

alrededor de 5 horas ago | 0

Is there a way to overlay a graph onto a video, plotting each successive point with each frame?
I recommend videofig() from the File Exchange. https://www.mathworks.com/matlabcentral/fileexchange/29544-figure-to-play-and-ana...

alrededor de 5 horas ago | 0

Compute operation with different index (part II)
It would be easier if you would switch over to table or timetable instead of using timeseries . filename = 'https://www.mathwor...

alrededor de 5 horas ago | 0

warning message using surf
We cannot tell what length(u) or length(v) or size(Xq) or size(Yq) is. You could get an error if size(Xq) is not the same as si...

alrededor de 5 horas ago | 0

How to change patient name?
P = zeros(256, 256, 263); for K = 263 : -1 : 1 petname = sprintf('%03d.dcm', K); info(K) = dicominfo(petname); So in...

alrededor de 6 horas ago | 0

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Solve taking too long, how to optimize code?
k = 180; length = .05; b = .01; T0 = 180; Tinf = 25; h = 25; Tsurr = 290; epsilon = 0.9; theta = atan((b/2)/length); ...

alrededor de 7 horas ago | 0

Can you give me the code for Stabilogram Diffusion Analysis (SDA)?
<https://isbweb.org/software/movanal/stamp/>

alrededor de 9 horas ago | 0

Unable to read UDP data with parfeval
When you use parpool (at least if you do not use the "threads" option, not sure about threads), then the workers are in a separa...

alrededor de 11 horas ago | 1

GUI new callback name
I can tell that you are using a GUI created with GUIDE. Edit ConvertMatLab_gui.m Near line 31 you will find lines % Begin in...

alrededor de 11 horas ago | 1

Each time menu() is called, it creates a new figure() .

alrededor de 12 horas ago | 0

Import txt file into MATLAB for Comparison of 2 files to measure bit errors
B1 = fileread('1.txt') - '0'; B2 = fileread('2.txt') - '0'; L1 = length(B1); L2 = length(B2); if L1 ~= L2 fprintf('fir...

alrededor de 12 horas ago | 0

how to decrease the x-axis from left to right
set(gca, 'XDir', 'reverse')

alrededor de 12 horas ago | 0

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Convert a Cell array with char and white spaces to Cell array with double without white spaces

alrededor de 12 horas ago | 0

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What " lo=3 " means in system option???
https://www.gams.com/34/docs/UG_GamsCall.html lo=3 means all of the output of the executable is to be written to "standard out...

alrededor de 22 horas ago | 0

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how to delete repeated rows in a table?
format long g M = [518460 3.322; 518460 -12.984; 518520 3.798; 518520 -10.28; 518580 7.763; 518580 16.851; 518640 5.959; 522225...

alrededor de 22 horas ago | 1

Matrix Dimensions must Agree
Your D_pca has 4 rows and an unknown number of columns. Your eigvects has 2 rows and an unknown number of columns. D_pca(:,1)*...

alrededor de 22 horas ago | 1

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multiply by two matrix
syms x n = [1.521, 2.66]; k0 = 1; h = [1.5e-6, 1e-6]; k = @(j) sqrt(n(j).^2*k0.^2-x.^2); M = @(j) [ cos(k(j) ....

alrededor de 22 horas ago | 0

Trying to compress a signal.
compressed_x = x(1:2:end);

alrededor de 22 horas ago | 0

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Plotting function, which includes a sum
When you provide a start value, you also have to provide a count -- even if you just provide inf as the count.

1 día ago | 0

absolute value in equality constraints
N = 5; var10 = optimvar('var10', N); var9 = optimvar('var9', N); var7 = optimvar('var7', N); prob = optimproblem; ABS = @...

1 día ago | 0

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How can I check if the columns of my matrix have value in common?
I am not certain what you are asking Either a value from the sixth column in all five first or subsequent columns. M = randi(2...

1 día ago | 1

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AppDesigner press 'Enter' key to stop edit-field type in

1 día ago | 0

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solve the equation for a large frequency range
Rsh=0.01*pi Lsh=5*10^-9 freq=1e+3:1e+8;%frequency range Rsh=0.01*pi; d=Rsh+(2*pi*freq*i*5*10^-9); factor = Rsh ./ d; In M...

1 día ago | 0

Add missing numbers of 0's and 1's in an array
M = [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0]; zstarts = strfind([1 M], [1 0]) zend = strfind([M 1], [0 ...

1 día ago | 0

Is it posible to change the number of digits Matlab works with?
You would have to use the Fixed Point Toolbox. This might require some modifications to QuTip toolbox; Fixed Point Designer woul...

1 día ago | 0

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matlab error: defined variable after local function definition
You have to move the lines x = linspace(0,500,1); T = linspace(0,500,1); m=0; sol = pdepe(m,@pdex1pde,@pdex1ic,@...

1 día ago | 1

asalam.A.
%x'y'z' + x'y'z + x'yz + xyz' [x, y, z] = ndgrid([false true]); x = x(:); y = y(:); z = z(:); actual_output = (~x & ~y & ~z...

1 día ago | 0