Community Profile

photo

Walter Roberson


Last seen: Today
47.298 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 2019
  • Most Accepted 2018
  • Most Accepted 2017
  • Solver
  • First Review
  • 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

View all

Contributions in
View by

Answered
Capture I2S data from FPGA board to MATLAB or Simulink
SoC Blockset Support Package for Xilinx Devices has https://www.mathworks.com/help/soc/ref/i2cmaster.html If I read specifica...

ongeveer een uur ago | 0

Answered
How do I derive a parametric slope symbolically?
I wanted to know if Matlab is able to take the argument diff(y,x) given that x and y are functions of t, and derive and then out...

ongeveer een uur ago | 0

| accepted

Answered
How do I name a structure or matrix with variable names (without using eval)
put everything into one variable. You can use dynamic field names for a struct, new fields added as you go. Or you can hold ever...

ongeveer 3 uur ago | 0

Answered
How to solve transcendental equation?
f(x) == c implies that f(x) - c = 0. You can construct the expression f(x)-c and use it with a root-finding function such as fso...

ongeveer 3 uur ago | 0

Answered
Error on uninstalling matlab
You can create that and then proceed so that it will exist to be removed. However, past experience shows that a bunch more such ...

ongeveer 6 uur ago | 0

Answered
Drawing a line without creating a legend entry
https://www.mathworks.com/matlabcentral/answers/25381-how-to-show-partial-legend-in-figure#answer_33306 You can set the IconDi...

ongeveer 6 uur ago | 1

| accepted

Answered
How to use 'fmincon' in hardware through simulink without any code generation error?
Generally speaking, Simulink Coder does not support matlab functions that you need Coder.extrinsic for. MATLAB Coder does suppo...

ongeveer 7 uur ago | 0

Answered
Failed to read xml error when using xmlread
filename = 'InputFileName.xml'; S = fileread(filename); SS = regexprep(S, 'encoding="ISO8859-', 'encoding="ISO-8859-', 'once')...

ongeveer 7 uur ago | 0

Answered
Vectorization of For loop
d = sum(b .* reshape(a, 1, 100, 100), [2 3]);

ongeveer 7 uur ago | 0

| accepted

Answered
Plotting a set of rings using a single function
r = 50; viscircles([0 0; 0 2*r; 2*r 0; 2*r 2*r], [r;r;r;r], 'color','k', 'linewidth', 1) If you need to be able to plot fewer ...

ongeveer 7 uur ago | 0

Answered
Help with Summation in Matlab
My guess: x_k = sum(diff(t_j(1:k)) .* V_xj(1:k-1) + x_1); but the x_1 does not make sense to me in that location: why would yo...

ongeveer 8 uur ago | 1

| accepted

Answered
Simplify Boolean/logical expression
simplify(S, 'steps', 10)

ongeveer 9 uur ago | 2

| accepted

Answered
Return a figures from different functions and subplot them
Your function returns the line handes. If you record them, then you can take each handle and set its Parent property to be the a...

ongeveer 10 uur ago | 0

Answered
Scattered data 4D interpolation
What interpolation do you need? For example you could do knnsearch() asking for the 2 nearest neighbours of each query point, ...

ongeveer 10 uur ago | 0

Answered
real clock seconds after 1 second delay in input
If you do not need high precision on it being every 1.0 seconds elapsed, then: max = 15; input = [0 0 0 0 1 1 1 0 0 0 1 1 1 1...

ongeveer 10 uur ago | 0

| accepted

Answered
How to extract RGB matrices from stacked TIFF file?
squeeze(mean(YourArray, [1 2])) squeeze(std(YourArray, [], [1 2])) These should give you a 3 x N array of values that are the ...

ongeveer 10 uur ago | 0

Answered
can calculate mean but not std
You accidentally created a variable named std

ongeveer 10 uur ago | 1

Answered
index multiple columns together on different critera
B=A(idx, :)

ongeveer 11 uur ago | 0

| accepted

Answered
i need to send a signal from one computer using matlab to another computer also running matlab through usb cable
In the general case, this is going to be a problem. USB is strictly a host / device ("master/slave") system. One of the two sid...

ongeveer 12 uur ago | 0

Answered
Running a matlab code through bash script
You need to find your MATLAB command line executable. For Mac it would be /Applications/MATLAB_R2020a.app/bin/matlab . You would...

ongeveer 13 uur ago | 0

| accepted

Answered
Undefined function or variable 'sym' error in MATLAB 2015b (GPTIPS)
The Symbolic Mathematics Toolbox for R2015b was release 6.3. It *did* have a function named sym, and syms was a slightly diff...

ongeveer 16 uur ago | 1

Answered
Logarithmic scale with a different base
log2(x) = log(x) *log(2) log(2) is a uniform scaling and since plots are scaled to fit available space, becomes irrelevant. ...

ongeveer 19 uur ago | 0

Answered
how can one create a new color?
You can create a function that returns the rgb triple. There are also some approaches involving a class with static methods that...

ongeveer 20 uur ago | 0

Answered
How to find overlapping in scatter plot
Within each of the 20 plots, each symbol has a pair of coordinates, one for x value and the other for y value. Now order the 20 ...

ongeveer 20 uur ago | 0

Answered
Code for 'Reverse a Vector'
That approach is wrong. Reverse of A B is reverse of B, followed by reverse of A. When you let either A or B be a scalar then...

ongeveer 22 uur ago | 0

Answered
Graph is Blank ? why?
"The graph of time vs ich isn't blank" At least one entry in ich is nan or infinite, and that is leading to the fft being all...

1 dag ago | 0

Answered
How can I use Xcode11 to be my compiler?
https://www.mathworks.com/help/coder/ref/codegen.html The problem at the moment is not xcode 11: the problem at the moment is...

1 dag ago | 0

| accepted

Answered
Locate particular portion in an image
d = size(img,1) - find(any(img, 2),1,'last') in pixels.

1 dag ago | 0

Answered
Write an url list in one column of a text file
You cannot solve that. Text files do not have hyperlinks, they just have text. If you write the whole thing in HTML standards...

1 dag ago | 0

| accepted

Load more