Walter Roberson
I do not do free private consulting. If you want to bring my attention to something, send a link to the MATLAB Answers location. I am currently caught up to T0099119; if you are waiting on a reply from me for an older issue, please send me a reminder.
C, MATLAB, Shell, Perl, Fortran
Spoken Languages:
English
Statistics
34 質問
55,141 回答
0 問題
1 解答
ランク
1
of 260,075
評価
123,168
貢献
34 質問
55,141 回答
回答採用率
52.94%
獲得投票数
16,060
ランク
78,211
of 111,637
貢献
0 問題
1 解答
スコア
20
バッジ数
1
貢献
0 投稿
貢献
0 パブリック チャネル
平均評価
貢献
0 Highlights
AVERAGE NO. OF LIKES
Top ten contributors whose answers received the most acceptances in 2021
Awarded to Walter Roberson on 01 Jan 2022
Reach 100000 reputation points. Honors the first contributor to reach this milestone, Walter Roberson
Awarded to Walter Roberson on 14 Aug 2020
Solve a problem for the first time
Awarded to Walter Roberson on 10 Jun 2017
Publish your first review
Awarded to Walter Roberson on 09 Oct 2019
The contributor whose answers received the most acceptances in 2019
Awarded to Walter Roberson on 01 Jan 2020
The contributor whose answers received the most acceptances in 2018
Awarded to Walter Roberson on 18 Jan 2019
The contributor whose answers received the most acceptances in 2017
Awarded to Walter Roberson on 02 Jan 2018
Contribute at least one answer each month for 36 consecutive months
Awarded to Walter Roberson on 20 Jul 2017
The contributor whose answers received the most acceptances in 2016
Awarded to Walter Roberson on 20 Jul 2017
The contributor whose answers received the most acceptances in 2015
Awarded to Walter Roberson on 20 Jul 2017
The contributor whose answers received the most acceptances in 2011
Awarded to Walter Roberson on 20 Jul 2017
The contributor whose answers received the most acceptances in 2012
Awarded to Walter Roberson on 20 Jul 2017
Content Feed
Is there any other function faster than sum(A,2) to get the sum of all rows?
Switching to columns can improve performance as it allows better use of hardware cache.
約5時間 前 | 0
unable to use solve or fsolve for linear system
those cross() calls each return a vector, and you compare the vector to [0 0 0] giving a vector result. You then try to store th...
約7時間 前 | 0
Can we choose step size rule in fmincon?
https://www.mathworks.com/help/optim/ug/optimizing-a-simulation-or-ordinary-differential-equation.html#btfixqo shows some contro...
1日 前 | 0
How to copy a matrix but skipping some row and column?
M = rand(24, 24); toskip = [1, 2, 4, 6, 8, 17, 19]; %version 1 M1 = M; M1(toskip, :) = []; M1(:, toskip) = []; size(M1) ...
1日 前 | 0
Matrix is close to singular or badly scaled. Results may be inaccurate.
You have enough duplicate t values that when you calculate "a" the rank does not reach 7; rank of a2*a does not reach 7, so your...
1日 前 | 0
| 採用済み
How to use use an anonymous function to fit data based on the fittype and fit functions.
There is no chance of fitting that function. fit() and fittype() pass in numeric data, and diff() of numeric data is always sma...
1日 前 | 0
Speeding up fread for random position in big file
In my experience, you can be more efficient on conversion of 12 bit data than what is done by fread() If memory serves raw = u...
1日 前 | 0
How can I get this code to work? I am trying to fit the equation that contains step and delta function to experimental data. But I am getting the following error.
Your Energy are in the 500 range. exp(pi*energy) overflows double precision. Your code then divides by large values, but you hav...
1日 前 | 0
Is it possible to decide which line is variable names in readtable?
Yes, you can do that. For example, variable_row = 3; datatable = readtable(filename, 'VariableNamesRange', variable_row); In ...
2日 前 | 0
| 採用済み
Double condition to find index
freq = 2000; %hz threshold = 20; %newtons significant_time = 50; %milliseconds significant_samples = ceil(significant_tim...
2日 前 | 1
| 採用済み
How to run a .exe file in other computers without Matlab?
https://www.mathworks.com/products/compiler/matlab-runtime.html has links to download mcr 8.5 (R2015a) In https://www.mathworks...
2日 前 | 0
Solve IVP with Taylor method of order
https://www.mathworks.com/matlabcentral/answers/1746100-whole-derivation-of-two-variable-differential-function#comment_2229660 a...
3日 前 | 0
| 採用済み
Error in the for loop of my function
The second parameter to symsum must be a scalar symbolic variable that will be summed over. However in your code, the second par...
3日 前 | 0
How do you create a scatter plot using select columns from app.UITable.Data?
scatter(TableName{:,2}, TableName{:,4})
3日 前 | 0
Is it possible to get the path of a file using uigetfile() ?
[filename, filepath] = uigetfile(); if ~ischar(filename); return; end %user cancel fullname = fullfile(filepath, filename); ...
3日 前 | 1
| 採用済み
eeg data to move a motor
Create a numeric array in which each row is a different (fixed-length) eeg sample, and in which you have another variable which ...
3日 前 | 0
| 採用済み
Extracting Categories from array
As the Tips says, C includes all categories in A, even if A does not contain any data from a category. To see the unique values...
3日 前 | 0
How can I determine the cluster of pixels in an image that are red or green and quantify how many of the clusters are green or red?
filename = 'https://www.mathworks.com/matlabcentral/answers/uploaded_files/1036195/image.jpeg'; YourRGBImage = imread(filename)...
4日 前 | 0
| 採用済み
Why there is an error in line 132? ( [Fit(1,j), tetaDE]=selectmodel2(Pop(:,j),NP,D,mphi,start,nodata,y,u);)
The following fails because you did not provide initbp() ui = [ -3.7287749e-001 1.5462074e-001 3.6396491e-001 -2.254015...
4日 前 | 0
| 採用済み
pair-was operation on 3D image(3D matrix)
You need to give up on the algorithm. If you were able to represent the results with one byte each, you would need 3435973836800...
4日 前 | 0
pair-was operation on 3D image(3D matrix)
findgroups() on the image. You probably are using uint8 so at most 256 different groups. Record the second output of findgroups(...
4日 前 | 0
Order of operation using ./
The order of operations is always left to right at the same precedence except for obscure behaviour for (^-), (.^-), (^+), (.^+)...
4日 前 | 0
I want to know how to create dynamic string array
for K = 1 : 5 out(randi(10)) = "entry #" + K; end out
4日 前 | 0
remove all strings from nested cell array
C = num2cell(randi(9,4,10)); C(randperm(numel(C), 4)) = {"string"}; C(randperm(numel(C), 4)) = {'chars'}; C for K = 1 : ...
4日 前 | 0
Whole derivation of two variable differential function
The equations are being careless about which variables depend on which variables, and on which variable the differentiation is w...
4日 前 | 0
Plotting points inside a circle
maxr = 5; %create data N = 20; r = rand(1,N) * maxr; theta = rand(1,N) * 2*pi; [x, y] = pol2cart(theta, r); %plot ...
4日 前 | 0
Current Directory for Generated Code
MATLAB Coder is designed to target embedded systems, so functionality that is not part of the C Standard Library is often not av...
4日 前 | 0
| 採用済み
Import part of dataset in a HDF5 file, by 'member' and/or 'logical array'
<https://fossies.org/linux/hdf5/examples/h5_compound.c> The approach seems to be to use the H5T utilities to create a prototy...
4日 前 | 0
Missing Library in Simscape
https://www.mathworks.com/help/physmod/sps/ref/thermistor.html You are looking in Simscape Electronics, but you should instead...
4日 前 | 0
You can also select a web site from the following list:
Americas
- América Latina (Español)
- Canada (English)
- United States (English)
Europe
- Belgium (English)
- Denmark (English)
- Deutschland (Deutsch)
- España (Español)
- Finland (English)
- France (Français)
- Ireland (English)
- Italia (Italiano)
- Luxembourg (English)
- Netherlands (English)
- Norway (English)
- Österreich (Deutsch)
- Portugal (English)
- Sweden (English)
- Switzerland
- United Kingdom (English)
Asia Pacific
- Australia (English)
- India (English)
- New Zealand (English)
- 中国
- 日本Japanese (日本語)
- 한국Korean (한국어)