Walter Roberson
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50,944 total contributions since 2011I 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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How can I convert an implicit function to an explicit function?
On my system at home, the following program takes less than 6 seconds. However, because I was iterating through versions during ...
4 hours ago | 0
Why are the legends appearing twice?
Your code is assuming that the audio only has one channel, but instead it has two channels in each file.
5 hours ago | 1
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How to verify if a row or a column or a cubic 3x3 have a repeated number for sudoku?
Suppose you store NaN for all slots that have not had anything written to them. Then extract the appropriate portion of the arra...
6 hours ago | 0
How can I find exactly the coordinates of the center of the yellow circle?
You can calculate the center of mass of the image. https://www.mathworks.com/matlabcentral/answers/363181-center-of-mass-and-to...
13 hours ago | 0
Cycle through graph marks
Create a cell array of linespec (character vectors indicating style and color and marker). Then each time you plot, index into a...
13 hours ago | 0
Frame Differecning help using matrices and pixels
Replace temp = im2gray(temp); temp2 = frames(:,:,:,l + 1); temp2 = im2gray(temp2); with temp = double(im2gr...
1 day ago | 0
Error using sym>convertChar (line 1537) when solving an ODE using laplace transform. How to fix the problem?
%%CODE %% Solving 2nd order ODE using laplace transform syms x(t) s X F Dx = diff(x,t); D2x = diff(Dx,t); eqn = D2x + 7*D...
1 day ago | 0
How can I sort through a set of tables and remove the duplicates?
isequal() can be used to test whether two table() have the same content and same variable names. For efficiency, you can group ...
1 day ago | 0
Error in my code
uigetfile has two outputs. The second one is the directory. You need to put it together with the file name to get the name to pa...
1 day ago | 0
Give a specific color to an interval of value
I suggest you use https://www.mathworks.com/matlabcentral/fileexchange/69470-custom-colormap
1 day ago | 0
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Save Geographic Player Figure as an image
fig = player.Parent; saveas(fig, 'ImageFileName.png')
1 day ago | 0
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How do i send image trought fsk modulator
Simulink reshape() block. https://www.mathworks.com/help/simulink/slref/reshape.html
1 day ago | 0
problem in cell matrix operations
Your current code would take 1 row from Coh, then the following 2 rows, then the following 3 rows, and so on. Is that what is de...
1 day ago | 0
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Solving system non-linear equations
syms x [1 4] sr = sym([0.05 0.1 0.5 1]); Eapp = sym([2.09 2.18 2.27 2.4]).*1e6; Ei = sym(2.55).*1e6; E0 = sym(2.14).*1e6;...
1 day ago | 0
Appending multiple variables onto a single file
dinfo = dir('*.mat'); filenames = {dinfo.name}; nfile = length(filenames); hasmap = false(nfile,1); for K = 1 : nfile ...
2 days ago | 0
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what does the function handles do in matlab?
handles is not a function. It is a struct. handles by itself has no special meaning; it could have been called anything. The c...
2 days ago | 1
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Any value (different values) I enter for TOLERANCE and ITERATION gives the same results(Answer( . It is supposed to give different answers . I don't know why this is occurring.
You exit the loop when you reach the tolerance. What happens if you exit the loop no later than 5 iterations? Then giving 20 in...
2 days ago | 0
Why does the Fourier transform of a vector cannot tranfroms back into it itself in an exact manner, through ifft(fft())?
Floating point round-off. format long g a = rand(16,1); b = ifft(fft(a))-a; plot(b) [min(b), max(b)] ans/eps The values ...
2 days ago | 0
Solving non-linear ODE
Your equation has 1/sqrt(t) and initial t of 0. That gives you 1/sqrt(0) -> 1/0 -> infinity at the start EP_equation functio...
2 days ago | 0
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Plot function cannot work normally
Your file E:\MATLAB Inc\MATLAB 2018B\toolbox\matlab\graphics\gobjects.m is corrupt. You will need to restore it from backup (if ...
2 days ago | 0
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too many input arguments error when i pass struct to my function
f = @(x)CostTimeDCal1; That says that when f is called, it should ignore its single input parameter and call CostTImeDCal1 with...
2 days ago | 1
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how to get keyboard in matlab
psychtoolbox http://psychtoolbox.org/ has several input methods that do not require use of figures to receive typing.
2 days ago | 0
Matlab gives error on empty line
The important part is Untitled line 43, which is the assignment to K_fc . On that line you have three places where you have ex...
2 days ago | 1
Remove Figure window from appearing at all in program
Correct, if you set a figure visibility off, then the sequence of code you use will not display it to the screen but will save i...
2 days ago | 1
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Index exceeds the number of array elements (2)
y(6) Your code expects 6 (or more) boundary conditions are going to be passed in y0 = [L*cos(alfa);L*sin(alfa)]; but ...
3 days ago | 1
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How to evaluate a function that has been saved to a variable
%provided that x is symbolic d1(x) = diff(f(x)) d2(x) = diff(f(x),2) d3(x) = diff(f(x),3)
3 days ago | 2
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Getting Input Error With Code
You need to rearrange your code. DissMale = abs(.50 - Crime_Male); DissFemale = abs(.50 - Crime_Female); [R,C] = size(DissMal...
3 days ago | 0
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Solutions are only valid under certain conditions
You can get four solutions. However, the solutions will be effectively useless, and the conditions under which they apply will b...
3 days ago | 0
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How to reconstruct a matrix?
x = [8, 9, -3, 9, 5, -4, -1, 3, 10, 10]; y = [-6; 4; 4; -2; 2]; z = [diag(y), x(1:5).'; x(1:6)]
3 days ago | 1
| accepted
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