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Walter Roberson


42,849 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
What is the MATLAB function for FILTER in direct-form I?
https://www.mathworks.com/help/signal/ref/dfilt.df1.html edit(which('dfilt.df1')) Will show you the exact code that is used.

약 20시간 ago | 0

Answered
how to extract data from the fixed-width-field format using fscanf or textscan
fileread into a character vector. regexprep to insert a space before every field. textscan the character vector.

약 23시간 ago | 0

Answered
Square wave with different amplitude for different time in number of cycles
250 * square(parametric_times, D) - 50 parametric_times would be such that the end of the parametric_time vector was 2*pi*numbe...

1일 ago | 0

Answered
Concatenate Tables with one variable having different lengths
Later versions than yours reject your input syntax because of ambiguity about options versus inputs. T1 = table({'Alpha'}, 33, ...

1일 ago | 0

| accepted

Answered
Undefined function or variable 'p1x'.
Your code requires six inputs. When you click on Run, you are providing zero inputs. Where are you expecting it to get the value...

1일 ago | 0

Answered
How to convert RGB to hsv?
for H = 1:ncols if T3(H) == 0 hprime(H) = 0; elseif T1(H) == R(H) hprime(H) = mod((G(H)-B(H))/C(H), ...

1일 ago | 0

Answered
How to compose functions with more than one output/input
In MATLAB, in every case where you have an expression of the form F(G(inputs)), it is not possible for F to capture all of the o...

1일 ago | 0

Answered
division of cfit objects
P = D./f1(x2);

1일 ago | 0

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Answered
imadjust returns error only supported for 2d-grayscal images
.jpg images are almost always color images. Your code acknowledges that when it does the gbird = rgb2gray(birds); In your comm...

1일 ago | 0

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Answered
How to use blockproc by location?
blockproc is a waste for this kind of task, but it can be done. You would specify a blocksize of 3 x 3 and an overlap of [1 1], ...

1일 ago | 0

Answered
i encountered an error saying Undefined function 'Linda' for input arguments of type 'char', while trying save a file and run a code
MATLAB is case sensitive. That code would not be recognized as a function because you used Function instead of function With th...

1일 ago | 0

Answered
Error: Undefined variable “vision” or class “vision.FasterRCNNObjectDetector” in Matlab 2019a.
You should not construct a fastRCNNObjectDetector yourself. You should call https://www.mathworks.com/help/vision/ref/trainfastr...

1일 ago | 0

Answered
Screen function does not seem to work properly.
https://github.com/Psychtoolbox-3/Psychtoolbox-3/issues/480#issuecomment-395840623 Timing is not going to work on Mojave, ever...

1일 ago | 0

Answered
How can I alterate a mask for Kmeans segmentation
M = true(size(im,1), size(im,2));

1일 ago | 0

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Answered
Loading Large .txt files
textscan() is more likely to succeed than some of the other alternatives. Most reliable would be to pre-allocate all of the sto...

2일 ago | 0

Answered
Why do I receive the error "Attempt to execute SCRIPT sisotool as a function"
restoredefaultpath rehash toolboxcache might solve the problem. If not then command which -all sisotool Unless you are using...

2일 ago | 0

Answered
Matlab Crushes when new .m file is added
Sometimes MATLAB can get confused and you need to rehash. This can happen in various ways, including if a file that is not on th...

2일 ago | 1

Answered
How to reconstruct a figure with a "line" variable
You cannot directly copy a line() object to a figure. You can copy a line() object to an axes, or you can copy an axes to a figu...

2일 ago | 0

Answered
I am working on a MATLAB GUI using App Designer, though perhaps my issue is similar to guide. What I would like to do is pass the output of one callback (button) into another.
The above suggests to me that you have a ui control button already that has the name loadmatButton and the handle to that is sto...

2일 ago | 1

Answered
How I can convert a single char array in a table with 3 columns?
Suppose you have the character vector stored in the variable S. Then: info_struct = regexp(S, '(?<Year>\d{4})\s+(?<Month>[A-Za-...

2일 ago | 0

| accepted

Answered
How do I read the number of nodes from a ssc file?
S = fileread('BSC019N02KS.ssc'); nodelines = regexp(regexp(S,'nodes.*?end','match','once'),'\r?\n','split'); if isempty(nodeli...

2일 ago | 0

| accepted

Answered
How to implement a generic 'filter' function using direct form I?
filterdf1 = @(a,b,x) filter( dfilt.df1(a,b), x); This is a three-argument filter function that uses direct type 1 form.

3일 ago | 0

| accepted

Answered
writetable with spaces on header
header = {'Last Name', 'Age', 'Smoker', 'Height', 'Weight', 'Blood Pressure'}; Tcell = [header; table2cell(T)]; writecell(Tcel...

4일 ago | 0

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Answered
Continuous Graph in a loop
i = 0:1:10; x = 1; B = x * ones(size(i)); mask = i <= 3; B(mask) = i(mask) + 2; plot(i, B,'-*')

4일 ago | 1

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Answered
How can I select items in a double list?
reshape(T_C,3,[]) Now the groups of 3 appear as columns.

4일 ago | 0

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Answered
How to remove a row based on text in a certain column?
mask = contains( string(DFTtable{:,3}), '[warning]'); DFTable(mask,:) = [];

4일 ago | 1

| accepted

Answered
Backslash error ''Warning: Matrix is singular to working precision."
1) Yes, the \ command has changed. Between those versions, the underlying LAPACK libraries were upgraded -- twice, I think. 2) ...

4일 ago | 0

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Answered
what is the construct algorithm of MATLAB's dfilt.df1 function?
edit(which('dfilt.df1'))

4일 ago | 0

| accepted

Answered
Why does Matlab require a Parallel computing toolbox in order to use more CPU cores?
Not quite. Matlab recognizes some patterns of operations and for sufficiently large matrices automatically calls high performanc...

4일 ago | 1

Answered
Confusion regarding uiswitch function in matlab GUI?
You cannot add uiswitch to GUIDE created GUI. GUIDE created GUI use "traditional figures". App Designer uses UI Figures though a...

5일 ago | 0

| accepted

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