John D'Errico
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What is the difference between A={1 2} and A = { '1','2'} and how to convert one from other ?
Think of it like this: 1 is a "number" as stored in MATLAB, as is 2. X = [1 2] whos X X is stored in double precision. We ca...
5 dagen ago | 0
comparison between two optimisation algorithms
There are very, very many ways to solve a computing problem. You have chosen one of them, and it worked for you. Is the choice...
9 dagen ago | 0
Strange behaviour of plot
Cute. If you try this in R2025a: small = 1e-7;plot([0,small,1],[0,small,1]) small = 1e-8;plot([0,small,1],[0,small,1]) (Sorry...
10 dagen ago | 0
How does Matlabs svd() function calculate the value of V?
UM, You seriously do not want to use X'*X to compute anything about the SVD. Yes, mathematically, it is the same. But this is no...
11 dagen ago | 1
icc rgb profile editing
You can use iccread and iccwrite. help iccread help iccwrite Having used iccread, you can modify whatever you wish, then writ...
11 dagen ago | 0
How to reduce the file size of MAT files?
NO. Rounding numbers will change nothing. MATLAB does not store double precision numbers in decimal form. So even though you thi...
17 dagen ago | 0
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select line by touching with mouse
"select curve?" Well, yes, in a sense. When you plot the curve, you can supply a ButtonDownFcn, so that when you click on the c...
17 dagen ago | 0
Fitting a blackbody curve with two variables - having issues with lsqcurvefit stopping and unsure how to use options effectively
Your data does not seem to fit terribly well to the model you propose. c=2.998e8; h=6.6261e-34; kb=1.38e-23; %wavelgnth (x...
18 dagen ago | 1
| accepted
How to generate all 2^n combinations of n choices from a 2-vector?
Simple enough. Don't use combinations. n = 3; t = dec2bin(0:2^n - 1) - '0' Easy enough to make that into a table if you so de...
21 dagen ago | 1
| accepted
Matlab 'try now' and contact customer service doesn't work
Answers is not customer support. In fact, we are generally not even employed at The MathWorks, though some TMW staff do visit th...
23 dagen ago | 0
| accepted
is readmatrix a built-in Matlab function part over every install after 2019a?
NO. Not for ANY release number. Some of those functions may have been introduced in different years, different releases. And if ...
24 dagen ago | 0
Constraints to a Second Order Curve Fit
You want to constrain the quadratic coefficient to be positive. But your data wants it to be a little bit negative. Effectively,...
ongeveer een maand ago | 1
Is vectorization worth the trouble with recent MATLAB?
Is vectorization worth it? Let me see. For example: Add 1 to every element of a vector. V = rand(1,1e6); % Which is itself high...
ongeveer een maand ago | 0
How to specify intervals of increasing, decreasing of a function in MATLAB
This can get fairly messy, if your function is carefully designed to cause you problems. For example, you may need to find a sin...
ongeveer een maand ago | 1
Not exactly the exact answer using Symbolic Math Toolbox
Your problem stems from a common mistake. Whaen you write this: syms t f = sin(t); frms = sqrt(1/(2*pi)*int(f^2,t,[0 2*pi]))...
ongeveer een maand ago | 1
How does the expfit function... functions
You may be confused. Well, let me say, almost certainly, you are confused. ;-) There is a difference between curve fitting, in ...
ongeveer een maand ago | 0
No results are showing in the symbolic math computation
First, you need to recognize MATLAB is case sensitive. Your code does not run, instead, it fails in several places. I fixed it, ...
ongeveer een maand ago | 0
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Solving ODE just for one time step
Then I fail to see the problem. You want only the solution at the end point. % A simple ODE. with y(0) == 1, the analytical s...
ongeveer 2 maanden ago | 0
Analyzing errors of a numerical Jacobian matrix of partial derivatives, as the finite-differencing step-size gets successively smaller,
I explained EXACTLY this in my last answer to your last question. Please read what I write and think about it. If you don't then...
ongeveer 2 maanden ago | 0
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How can I reduce the "method error" with my central-difference method, when estimating a Jacobian matrix of partial derivatives?
This is a complex question, with possibly no perfect answer. For example, suppose you have a Newton method, that employs a fini...
ongeveer 2 maanden ago | 3
Better package manager abstracted away from matlab versions
Why don't they have the perfect set of tools, exactly as you want them to have been written? Because MATLAB was designed to make...
ongeveer 2 maanden ago | 0
Generate n random numbers between 0.1 and 0.9 without repetition
There are always many ways to solve a problem. Here is mine: % generate the set of ALL possible combinations. There are not man...
ongeveer 2 maanden ago | 0
How to get real root of a function using fminbnd?
It sounds like you want to see the result: (-1)^(4/3) == 1 To do that, you want to use nthroot, by splitting the fraction...
ongeveer 2 maanden ago | 0
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solving numerically non-linear equation , code below does not work
What does not work? This is just a basic Newton-Raphson method. First, what are the functions for your test problem? x^2 + y...
ongeveer 2 maanden ago | 1
Find the range of duplicates in a sorted element
I'll create a longer vector, with a few duplicates. V0 = randi(8,[1,15]) V = sort(V0) Now you want to know where the dups liv...
ongeveer 2 maanden ago | 0
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What do you think of my numerical Jacobian, using the central-difference method?
What do we think of it? I'm sorry, but blech! Why? Don't number all of your variables! Don't create long lists of numbered var...
ongeveer 2 maanden ago | 1
Inverting an 8x8 symbolic matrix
What nobody ever seems to understand is that a symbolic inverse of a matrix like this grows exponentially in complexity. Many th...
ongeveer 2 maanden ago | 3
Is there any precomputation step on A'*(.)*A if matrix A is known, to speed up matrix computation A'*B_i*A in matlab with B_i denpends on the previous matrix B_{i-1}.
A is known and fixed, and apparently large, else you would not care about speed. The amount of memory on your laptop is irrelev...
ongeveer 2 maanden ago | 0
How to identify algorithm time complexity?
It is not at all trivial to determine the time complexity for SOME algorithms, at least not from merely knowing the method emplo...
ongeveer 2 maanden ago | 0
Where to Find a Dataset of High-Quality MATLAB Code for Training an LLM?
Looking at your question a second time, it is about MATLAB in a sense. in that you are looking for a repository of code to train...
2 maanden ago | 0
