Community Profile

photo

Walter Roberson


42,881 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.

Contact

Walter Roberson's Badges

  • Most Accepted 2018
  • Most Accepted 2017
  • 36 Month Streak
  • Most Accepted 2016
  • Most Accepted 2015
  • Most Accepted 2011
  • Most Accepted 2012
  • Most Accepted 2013
  • Thankful Level 4
  • Grand Master
  • Revival Level 4
  • Knowledgeable Level 4
  • First Answer
  • Solver

View details...

Contributions in
View by

Answered
Why do I get this error since there is only one function?
This happens when a script file with that name contains a function definition with the same name. Which can also happen in what ...

3 hours ago | 1

Answered
Many functions in a large script file
"I am wondered how can I add nested functions in a parent function in a while loop. Is that possible?" No. functions cannot be ...

9 hours ago | 0

| accepted

Answered
cannot call m-file in another m-file
y = 2x + 3; 2x is not a valid variable name in MATLAB, and it is not a valid way to write a number in MATLAB. Like the error m...

9 hours ago | 1

| accepted

Answered
Clustering Calculating total value
C1 = C(1,1:2); C2 = C(1, 3:4); X = YourArray - C1;

11 hours ago | 0

Answered
Solver execution time is very slow.
tic syms a1 a2 a3 eqns = [a1 + 0.01 * (a2 + a3) - 5, a2 + 0.01 * (a1 + a3) - 6, a3 + 0.01 * (a2 + a1) - 7]; sol = solve(eqns,...

11 hours ago | 0

Answered
Inquiry MISRA C 2012 6.1
You have a problem. http://port70.net/~nsz/c/c89/c89-draft.html#3.5.2.1 A bit-field may have type int , unsigned int , or sig...

11 hours ago | 0

Answered
how to take mean of every second data in a minute and an hourly?
TT2 = retime(TT1, 'minute', @std);

11 hours ago | 1

Answered
How do I convert to Mex from Cpp using Xcode ver 10
Your SegmentBoneDP.cpp file is the source code. If you need something that converts C++ code into MATLAB code, then you are usi...

14 hours ago | 1

| accepted

Answered
How to solve a system of two non-linear equations symbolically
sol = solve(L0 -1 +a*L1^(a-1) -a*A*L0^(a-1)==0, L1 -1 -a*L1^(a-1) +a*A*L0^(a-1)==0,'returnconditions',true); sol = stru...

15 hours ago | 1

Answered
How to show the legends of this plot?
Record the handles of the objects you are going to produce legend() entries for. Pass those handles to legend() as the first par...

1 day ago | 1

Answered
How to fix MATLAB errors arise from changing the search path?
"I usually saved my projects in C:\Program Files\MATLAB\R2016a\bin" You have corrupted MATLAB . You need to move your projects ...

1 day ago | 0

Answered
How do I change the color of the markers in the legend in a scatter plot with colormap?
Most of the time, using legend() together with scatter() will not give you the results you want. The work-around is to deliber...

1 day ago | 0

Answered
Leave out dot notation in table variables
The closest MATLAB equivalent is import but it only applies for packages https://www.mathworks.com/help/matlab/matlab_oop/scopin...

1 day ago | 0

Answered
How to copy every 500 rows to a new variable?
result = squeeze(cellfun(@transpose, num2cell(reshape(YourMatrix.', size(YourMatrix,2), 500, []), [1 2]), 'uniform', 0)); This ...

1 day ago | 0

Answered
how to take mean of every second data in a minute and an hourly?
We recommend creating timetable() and using the retime() function.

1 day ago | 1

| accepted

Answered
Error: Function definitions are not permitted in this context.
It is never valid to copy and paste a "function" definition to the command line. It is also not valid to eval() a character vect...

1 day ago | 0

| accepted

Answered
How can we start different sessions simultaneously?
"Is there a way to start two different sessions simultaneously?" No. And parfor or spmd will not help for this purpose. Startin...

1 day ago | 0

Answered
How to remove a particular frequency in the fft code?
[~, idx] = min(abs(f - 10.1)); %which bin is closest to 10.1 ? Y(idx) = 0; %zero that bin Y(end-idx+2) = 0; %zer...

1 day ago | 0

| accepted

Answered
How to Give Column Names to MATLAB Table Dynamically
Column names must be valid matlab variable names. colnames = "AD" + T; The AD can be changed to any valid prefix of a var...

1 day ago | 0

| accepted

Answered
I need help ploting a graph
y=5*(1-0.5772156649.^(-x/4.8))

2 days ago | 0

| accepted

Answered
Using Textscan on non-uniform data
fid = fopen('HS_full_18md_nam_outputs.txt'); fgets(fid); %skip header ctl = fscanf(fid, '%f%f', 2); Nt = ctl(1); Ns = ctl(...

2 days ago | 1

Answered
How should I randomly generate pairs of non-identical natural numbers that should also be non-repeating?
[A, B] = ndgrid(range); mask = A==B; A(mask) = []; B(mask) = []; N = length(A); p = randperm(N, 20); pairs = [A(p); B(p)].'...

2 days ago | 1

| accepted

Answered
How can I only keep keys that have the smallest value pair in a matrix?
[g, val] = findgroups(A(:,1)); B = [val, accumarray(g, A(:,2), [], @min)];

2 days ago | 0

Answered
Setpath error: the path file pathdef.m might be read only
MATLAB generally creates a writeable pathdef.m when it is installed, but not always. Sometimes pathdef.m ends up in a directory ...

2 days ago | 0

Answered
install App with image-component in older version Matlab
uiimage() cannot be used in any release before R2019a.

2 days ago | 0

Answered
What is the max image size Matlab OCR can process
"What is the largest size image Matlab's OCR can process?" 140737488355327 bytes. Call it 6 1/2 million by 6 1/2 million RGB.

2 days ago | 0

| accepted

Answered
loading excel cell in matlab
vel_data=dir('*.mat'); so vel_data contains information about .mat files WL_data=dir('*.xlsx'); so WL_data contains informati...

2 days ago | 0

Answered
How do I explain the random functions to my professor?
"Also, it will be different from picking one value each from A,B,C for 5 times compared to picking all 5 from A, then moving on ...

2 days ago | 4

Answered
What is the meaning of following code?
size(Residuals,1) is the number of rows in the Residuals array. 1:2:size(Residuals,1) is the odd-numbered rows. [1:2:size(Residu...

3 days ago | 0

| accepted

Answered
I have IgorTime data in which time:units = "seconds since 1904-01-01". I would like to convert this seconds to datevc.
datetime(T/86400,'convertfrom','excel1904')

3 days ago | 1

| accepted

Load more