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Walter Roberson


43.970 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
How can i fix the error "Error using inline Input must be a character vector." and "Error in (line 9) g=inline(f);"
inline can only be used with character vectors. Your f is a double precision scalar. If you were to format it into a characte...

1 giorno ago | 0

Answered
solving equation contains lambertw function
The Symbolic Toolbox has lambertw

1 giorno ago | 0

Answered
How to clear file name and file path information?
Use '' or "" as the value instead of []

1 giorno ago | 0

| accepted

Answered
why ismember({struct.name},{'*.mat'}) returns zero while struct.name='basevalues_Mean_r.mat'?
ismember() never does wildcarding. It only does exact matches. regexp() does matching but the handling of wildcards is differen...

2 giorni ago | 1

| accepted

Answered
How to find minimum number of largest square of 1 in an 2D bool matrix
D = bwdistgeodesic(logical(YourImage), ~YourImage); Now iterate. if there are no finite values in D, break the loop. Find the l...

2 giorni ago | 0

Answered
how can i convert 1xn to mxn matrix ?
Use persistent variables in your function. The first 19 times the function is called, just store the 100 values passed in. The 2...

2 giorni ago | 0

Answered
Mat2Cell error when splitting an image up into smaller images
function blockImages = splitImageIntoBlocks(image, blockSizeRow, blockSizeCol) % blockSizeRow: Rows in block % blockSizeCol: C...

2 giorni ago | 0

| accepted

Answered
How can I print each piece of data in the following colum while iterating through a for loop with fprintf
It is possible to build up tables one column at a time. In order to do so, you need to work with character arrays and sprintf, o...

2 giorni ago | 0

Answered
'trapz' to find area under curve not working
x=length(y) is a scalar value, just the length. You then pass that one length as the X coordinates and pass all of y as the Y co...

2 giorni ago | 0

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Answered
Extract data from cell
YourCell(~cellfun(@isempty,YourCell))

2 giorni ago | 0

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Answered
Getting rid of a for loop
value1 = find(input(1:end-2) > input(2:end-1) & input(2:end-1) < input(3:end)) + 1; value2 = input(value1);

2 giorni ago | 1

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Answered
The crtrp function from the genetic-toolbox doesn't work
Line 34 can be deleted.

2 giorni ago | 0

Answered
difference between two programs
X=imread('mosque.jpg'); The great majority of .jpg are RGB (grayscale is possible but very rare.) [n,m]=size(X); size() of a...

3 giorni ago | 0

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Answered
X and Y must be same length, however they already are?
You do not store any x values, so it is [] after the reading loop.

3 giorni ago | 1

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Answered
Why does solve() parametrize the results in the conditions?
Your nonnegative and positive constraints together with the ^2 impose boundaries. The equation has to be solved in ways that the...

3 giorni ago | 0

Answered
How can I solve the error of {Undefined operator '.^' for input arguments of type 'optim.problemdef.OptimizationExpression'}?
You cannot fix that problem in that release. The first release or two of Problem Based Optimization supported only linear proble...

3 giorni ago | 0

Answered
How do I save handles struct from a GUI as a .txt file in a way I can then uploaded back to the GUI?
If you do not care whether the file is human readable, then you can try using https://www.mathworks.com/matlabcentral/fileexchan...

3 giorni ago | 0

Answered
Using a tolerance in X with fzero function (by default the tolerance is evaluated on Y axis).
There is no mathematical way for fzero to be able to reliably detect that. You are asking that if you are currently at positio...

3 giorni ago | 0

Answered
How to get out of the for cycle and start all over again?
a = 1; while true B = a*23+54 ; if B < 89 a = a+1; continue; end end Or more cleanly, a = 1...

3 giorni ago | 0

| accepted

Answered
How to avoid permutation condition in Genetic Algorithm?
Use A and b constraints to enforce that the values are in sorted order. x(1) < x(2) if [1 -1]*x(1:2).' < 0 so A = [1 -1 0 0 0 0...

3 giorni ago | 0

Answered
Ploting stack of matrices
If you have x being a 100 x 1 matrix, and y being as 100 x 4 x 4 matrix, then plot(x, reshape(y, size(y,1), [])) This would cr...

4 giorni ago | 0

Answered
ode45 error **help please**
ode45(@ex3_2ndorder, stuff You probably left out the @

4 giorni ago | 0

Answered
I don't have function "deeplabv3plusLayer" in Matlab 2019a
It was introduced in R2019b

4 giorni ago | 1

Answered
Where does the getappdata() function save its data?
getappdata returns its output as regular output, same as a+b returns its output. You would want to store the output or use it in...

4 giorni ago | 0

Answered
What function fits my data...?
There are an infinite number of functions that explain your data perfectly to within rounding error. It would be the infinity of...

4 giorni ago | 0

Answered
Tilde character underneath a letter in Matlab charts
If you do not need latex then use 'a' followed by U+0330. Unicode can be used for interpreter none or tex

4 giorni ago | 0

Answered
Create a function that is the sum of an arbitrary number of functions
@(t) sum(cellfun(@(H) H(t), Bi))

4 giorni ago | 0

Answered
different version of MATLAB same license server
Yes. Each license server can serve licenses for any older version. Also, each license for a particular version is also valid ...

4 giorni ago | 0

Answered
implement first kind bessel function
Not exactly. Although -J1 is the derivative of J0, that does not mean that J1 = -besselj(1,x), it means that J1 = besselj(1,x) a...

4 giorni ago | 1

| accepted

Answered
What is the best syntax to use for dVph/dλ?
No, if you are working numerically use gradient() If you are working symbolically then diff(Vph(lambda), lambda)

4 giorni ago | 0

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