Walter Roberson

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49,364 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
Optimization issue, always different results?
Yes, it is normal for different algorithms for lsqnonlin to give different results. lsqnonlin is not a global optimizer and the ...

2 hours ago | 0

Answered
how to do smoothen this graph
f=5000; C=[2.000 1.000 0.665 0.500 0.400]; Xc=[15 30 48 58 76]; %% a data=C*10^-6*f eq=1./data %% b figure subplot(4...

4 hours ago | 0

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Passing individual elements of an array into a function
temp = num2cell(arr(1:end)); myfun(temp{:}) This situation is most common when the user has used matlabFunction to convert a s...

4 hours ago | 1

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I need help in splitting an array
The following code is only valid for A up to 96 entries, after which it will run out of single-character variable names to assi...

4 hours ago | 0

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Extract subsets of consecutive entries in a matrix
n = 100 p = 4; matrix = rand(n, p); selected = select_consecutive_rows(matrix, p+1); selected function selected = select_...

5 hours ago | 0

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Undefined function or variable 'lgamma'.
I see relevant discussion at https://github.com/wichmann-lab/psignifit/issues/4 . The implications there are that you are pickin...

5 hours ago | 0

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do we have relation between LommelS2 and MeijerG in matlab?
https://www.maplesoft.com/support/help/Maple/view.aspx?path=LommelS1 and scroll down to near the bottom to see the conversions...

19 hours ago | 0

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Code generation with external variables
You can translate that pretty directly into a MATLAB function block that uses some persistent variables. function triggered = f...

19 hours ago | 0

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matlab piece wise function
(x>-0.5) So x is greater than -1/2 (x<0.5+0.5.*t) and x < 1/2 + t/2. If x is not in that range the the overall result will b...

20 hours ago | 1

Answered
How to convert a 2D image (which are pixel values plotted using 'imagesc') into a 3D surface plot?
IMG1 = imread('cameraman.tif'); IMG2 = imread('flamingos.jpg'); %size(IMG1), size(IMG2) [X1, Y1] = meshgrid(1:size(IMG1,2), 1...

20 hours ago | 0

Answered
How to avoid unwanted line break in figure title?
t = [nameSources{1} ' ' valParameter{1} '%']; or t = nameSources(1) + ' ' + valParameter(1) + '%';

22 hours ago | 0

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Answered
'setprecision', 24
system_dependent('setprecision')... I seem to recall that it only ever had effect on windows and only for some of the older rele...

22 hours ago | 0

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function handling and calling
For e.g (x*t)-t*(x) should cancel out each other but it is writing it as same (x*t)-t*(x) There are two possibilities that...

24 hours ago | 0

Answered
how to convert struct to sym
for S=1:nX solutions{S}=solve(Qo(S)*(1+R(S))*(No(S)-N)-V*(a*J+((X(S)*k*N)/(Kn+N))),(sqrt((Lstar^1.76)+5.2*(Nstar-Nstar_mi...

1 day ago | 0

Answered
While Adding two matrix using App Designer, I am getting this error "Undefined function 'Plus' for input arguments of type 'table' "?
When you readtable you should not assume that all of the entries are numeric, or that all of the variables are present in both ...

1 day ago | 0

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Answered
How to apply a random Crossover (Arithmetic/Scattered/Two-point) in Genetic Algorithm using auto-generated file from Optimization Toolbox ?
options = optimoptions(options,'CrossoverFcn', @MyCustomCrossover) function varargout = MyCustomCrossover(varargin) cr...

1 day ago | 0

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Answered
App designer Problem : error matlab.ui.control.internal.model.AbstractNumericComponent/set.Value (Line 111 ) 'Value' have to be double scalar
app.x is not initialized, so it defaults to empty. fx = (app.x)^2 + app.x; value^2 is only valid if the value...

1 day ago | 0

Answered
Help me with building a model in Simulink
https://www.mathworks.com/matlabcentral/answers/358859-index-for-array-max-or-min-in-simulink-without-variable-size-signal-or-ma...

1 day ago | 0

Answered
format of an output of a function
ismember(A,B).' you would have received a row vector if A was a row vector ismember(A(:).',B)

1 day ago | 0

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Answered
Question about plotting graph.
For some T values, there are two solutions; which one you get depends upon the starting point for your search. t0 = linspace(27...

2 days ago | 1

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Answered
Convert image to black white without using gray bands(hint, by using for matrix);
https://www.tutorialspoint.com/dip/grayscale_to_rgb_conversion.htm See the "Weighted method" section; it gives a formula for c...

2 days ago | 0

Answered
How to fit a dress on human body automatically ?
If all you have is a picture of a piece of clothing, and a picture of a person, then you cannot reliably fit the clothing on the...

2 days ago | 0

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CloseRequestFcn of GUI not working with wrong current folder
You have coded figure1_CloseRequestFcn in a way that calls upon a function that you expect to be in the MATLAB path, but turns o...

2 days ago | 0

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Answered
How to prevent the function rmnode from refreshing the nodes' labels?
If you use graph() or digraph() objects, then Nodes is a table, and you can add additional properties to the table including per...

2 days ago | 1

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Answered
matlab programing or code
I learned my first programming language pretty quickly, right through the complete textbook including the "Advanced" parts in ab...

2 days ago | 0

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Answered
Loop through list of variable in workspace to get and store in matrix
selected={'A', 'B' 'C'}; filename = 'YourFile.mat'; vars_present = who('-file', filename); present_mask = ismember(selected...

2 days ago | 0

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Answered
How to convert this equation into matlab coding
Symbolic toolbox if you have it. But code the max() as piecewise() The max() cannot be directly handled by the numeric ode ro...

2 days ago | 0

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Answered
Index in position 1 exceeds array bounds (must not exceed 1). Please help me
x=app.DefinalaEcuacionDiferencialEditField.Value; x is probably going to be a character vector. f=eval(x);%Permite eva...

2 days ago | 0

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How to deal with the missing information on vmrk file?
https://pressrelease.brainproducts.com/markers/ describes the file format There is no support for defining markers as existin...

2 days ago | 0

Answered
Can i do Wavelet coherence in MATLAB R2014a ?
To use that function in R2014a what you should do is become a Mathworks employee or intern and get authorization to back-port th...

2 days ago | 1

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