Community Profile

photo

Walter Roberson


Last seen: Today Active 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.

Statistics

All
  • Roberson Cup
  • Most Accepted 2019
  • Solver
  • First Review
  • Most Accepted 2018
  • Most Accepted 2017
  • 36 Month Streak
  • Most Accepted 2016
  • Most Accepted 2015
  • Most Accepted 2011
  • Most Accepted 2012
  • Most Accepted 2013

View badges

Content Feed

View by

Answered
Matlab r2020a becomes extremely laggy after several hours
If you are using any window management program such as Magnet, then disable that or configure MATLAB to be excluded. If you h...

1 hour ago | 1

Answered
why do I get a strange result with griddata cubic?
This is expected behavior when there are sharp edges, especially with a surrounding flat area. B-- | -A- Es...

3 hours ago | 0

Answered
How to create a structure array?
findgroups(), and use the group numbers to splitapply() where the work function is @(x){x} . The results should be a cell array....

3 hours ago | 0

Answered
append rows of a table
The general solution is to vertcat or [;] a cell array that has the same number of columns that as the table has variables. This...

3 hours ago | 0

Answered
gui size problem on another computer
https://www.mathworks.com/help/matlab/ref/matlab.ui.control.uicontrol-properties.html#d123e1411378 The default Units for uicon...

1 day ago | 0

Answered
How to change the default range of hyperparameters in fitcecoc function?
In the section https://www.mathworks.com/help/stats/fitcecoc.html#d123e297982 Set nondefault parameters by passing a vector of...

1 day ago | 0

Answered
how to calculate the gamma function when the variables are the complex numbers?
The Symbolic Toolbox can calculate it. format long g a = sym(complex(randn, randn)) g1 = gamma(1/4 + 1/2*1i*a) double(g1)

1 day ago | 0

| accepted

Answered
how to use setvartype on a table that is already existing
Can someone tell me how to set all the variable types to one uniform type using setvartype function? That is not possible. setv...

1 day ago | 0

Answered
I want to shorten a string.
If it is a string() object then see extractAfter()

2 days ago | 0

Answered
Which Processor and how much RAM is required?
https://www.notebookcheck.net/AMD-Ryzen-7-5700U-Processor-Benchmarks-and-Specs.510416.0.html That Ryzen does support AVX2. If...

2 days ago | 0

Answered
Support vector machine for multi-class
https://www.mathworks.com/help/stats/classificationecoc.html#bue3o6e-12 So use one row for each sample, and the columns are th...

2 days ago | 0

| accepted

Answered
how to create a variable without assigning a value to it and also the variables shouldnt be symbolic variables
syms e d m = [27.5084 -10.7668 -9.7727;-20.6533 15.8060 14.8502]; k1 = m * e; %not used k2c = arrayfun(@(V) tf(V,[1 ...

3 days ago | 0

| accepted

Answered
storing loop values in a matrix
N = 10; iters = 5; column = randi(9,N,1) results_of_loop = zeros(N, iters); for K = 1 : iters results_of_loop(:,K) = co...

3 days ago | 0

| accepted

Answered
i need help writing code in matlab that will plot data of 4 different variables onto one graph
format long g data = { 'earth', 14.3145, 2756.22, 228.060 'venus', 15.0717, 3580.80, 224.65 'mars', 13.7819, 27...

3 days ago | 0

Answered
Efficient way to implement this UDP protocol for loopback IP
udp does not synchronize: is is completely happy to send of 1000 packets from a source in the time before the first of them is p...

4 days ago | 0

| accepted

Answered
Can I substitute a particular expression?
There are two scenarios: 1) syms k sigma positive A = [k, k^(1/2), k^(3/2), k^(5/2)] B = subs(A, k, sigma^2) That is, if ne...

4 days ago | 0

| accepted

Answered
How do I convert this math expression to MATLAB code?
U = arrayfun(@(idx) randn(m,m), 1:2*T, 'uniform', 0);

4 days ago | 1

| accepted

Answered
Iterative solution for a non-linear equation
format long g Sa = 2.7956; A = 2.24; B = 0.5547; Gamma_p = @(ag_p) A+B*ag_p; f = @(ag_p) ag_p*Gamma_p(ag_p) - Sa; z = fz...

4 days ago | 0

| accepted

Answered
Is Oracle Java JRE license included with Matlab license?
The situation might be different on Windows, but on Mac and Linux, version -java and that version is the last free one accordi...

4 days ago | 0

| accepted

Answered
How can I reference the content of an UIAxes
Not directly, not without some careful analysis of properties. The issue is that live video, and video files, and screen shots,...

4 days ago | 0

Answered
how to create an array of plots in App designer
In the lines app.H_PlOT.XData(1:app.index) = 1:app.index; app.H_PlOT.YData(1:app.index) = 1:app....

4 days ago | 0

Answered
Removing moire pattern from an image
filename = 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/210517/MatlabThing.png'; I = imread(filename); I=im...

4 days ago | 0

Answered
Problems with 'uigetfile' and 'imread' in simple MATLAB Web App
My interpretation would be that libTiff on the server is not the same as libTiff on the online version. In particular if you a...

5 days ago | 0

Answered
Incorrect dimensions for matrix multiplication
XI= zeros(1,nmax); YI= zeros(1,mmax); XI and YI are the same size. S2= S2+(4*XI*YI*ZI)*((T_ini-T_ts)*exp(-alpha*landa2(n,m,l...

5 days ago | 0

Answered
skipping files in for loop
Change if ~isempty(w)%If h is not empty, then its a reference image, calculate to if ~isempty(w{s})%If h is not empty, the...

5 days ago | 1

| accepted

Answered
How to extract the annotation file of XML data using MATLAB?
(tested) T = readtable('000001.xml'); img = imread('000001.jpg'); x = T.xmin; width = T.xmax - x + 1; y = T.ymin; high = T...

5 days ago | 0

| accepted

Answered
How to write a range of numbers in MATLAB?
theta = (0:60).'; and remember to use cosd() and sind() Notice the .' there: it is transposing the 0:60 from a row vector into...

5 days ago | 0

Answered
Unrecognized property 'Title' in heatmap function
which -all heatmap I suspect that you are using a third party heatmap function

5 days ago | 0

| accepted

Answered
Error using actxserver(line 90). Server creation failed. Invalid ProgID 'Excel.Application'. with MAC and Matlab R2017b
https://www.mathworks.com/help/matlab/ref/actxserver.html says that actxserver() is only available for Windows. The Mac version...

5 days ago | 0

Answered
Trying to transmit and receive a simple waveform via loopback on B210 radio
Not really, no. See https://www.mathworks.com/matlabcentral/answers/336589-how-can-i-simultaneously-transmit-and-receive-using-...

6 days ago | 0

Load more