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Answered
compute the inverse sine of the sine of 45 degrees and assign the answer in radians to a variable named a.
Well, you are not doing anything overtly wrong. I would guess the answer is a subtle one, and reflects an error on how the test ...
compute the inverse sine of the sine of 45 degrees and assign the answer in radians to a variable named a.
Well, you are not doing anything overtly wrong. I would guess the answer is a subtle one, and reflects an error on how the test ...
1 day ago | 0
Answered
what is the highest number that matlab can handle. (especiially for the 3x+1 problem). i am trying to do the seed 10^310 i am not getting the plot or output why?
Your question should not be the highest number, but the largest INTEGER MATLAB can handle as a double. That would be 2^53-1. An...
what is the highest number that matlab can handle. (especiially for the 3x+1 problem). i am trying to do the seed 10^310 i am not getting the plot or output why?
Your question should not be the highest number, but the largest INTEGER MATLAB can handle as a double. That would be 2^53-1. An...
2 days ago | 1
Answered
Cap Maximum ODE solve time
Simpler is to just set the maximum number of evals or iterations. This way you don't need to do anything special, just set a fla...
Cap Maximum ODE solve time
Simpler is to just set the maximum number of evals or iterations. This way you don't need to do anything special, just set a fla...
5 days ago | 0
Answered
The below code takes much time to just compute till N=5. But I wanna know how to do it for N=100 or more a bit faster.
I want a bright red new Ferrari in my driveway for Christmas. Its not gonna be there of course. But we all want things we can't ...
The below code takes much time to just compute till N=5. But I wanna know how to do it for N=100 or more a bit faster.
I want a bright red new Ferrari in my driveway for Christmas. Its not gonna be there of course. But we all want things we can't ...
11 days ago | 0
Answered
How to merge red and blue images on white background with transparency
Easy enough, in a very lazy way too. If you kow how to do what you want with a black background, then make it so. And then back....
How to merge red and blue images on white background with transparency
Easy enough, in a very lazy way too. If you kow how to do what you want with a black background, then make it so. And then back....
12 days ago | 0
| accepted
Answered
How to use arrayfun with built-in Matlab functions where the variable parameter is passed with 'Name', 'Value'?
I see this soooo often, people thinking arrayfun is a good way to speed up code. But, is it, really? Arrayfun is a nice tool to ...
How to use arrayfun with built-in Matlab functions where the variable parameter is passed with 'Name', 'Value'?
I see this soooo often, people thinking arrayfun is a good way to speed up code. But, is it, really? Arrayfun is a nice tool to ...
16 days ago | 1
Answered
solving system of equations
There is absolutely no need to use an iterative solver!!!!!!!! The idea is to remove the absolute value from your problem, and ...
solving system of equations
There is absolutely no need to use an iterative solver!!!!!!!! The idea is to remove the absolute value from your problem, and ...
21 days ago | 0
Answered
Can not read MAT file in another language
My guess is Julia can read a .mat file created for an earlier release of MATLAB. Looking at the help for save, you can specify a...
Can not read MAT file in another language
My guess is Julia can read a .mat file created for an earlier release of MATLAB. Looking at the help for save, you can specify a...
22 days ago | 0
| accepted
Answered
Trying to do an fsolve via an anonymous function
You say you want to use fzero. But you need to understand that fzero is a ONE variable solver. It CANNOT solve a multi-variable ...
Trying to do an fsolve via an anonymous function
You say you want to use fzero. But you need to understand that fzero is a ONE variable solver. It CANNOT solve a multi-variable ...
24 days ago | 0
Answered
Precision lost when combining Int32 integers with single precision numerical numbers
Why is MATLAB set up this way? Because you can't please all of the people, all of the time. Suppose a numeric vector could have ...
Precision lost when combining Int32 integers with single precision numerical numbers
Why is MATLAB set up this way? Because you can't please all of the people, all of the time. Suppose a numeric vector could have ...
26 days ago | 3
| accepted
Answered
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...
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...
1 month ago | 0
Answered
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...
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...
1 month ago | 0
Answered
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...
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...
1 month ago | 0
Answered
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...
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...
1 month ago | 1
Answered
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...
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...
1 month ago | 0
Answered
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...
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...
1 month ago | 0
| accepted
Answered
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...
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...
1 month ago | 0
Answered
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...
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...
1 month ago | 1
| accepted
Answered
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...
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...
2 months ago | 1
| accepted
Answered
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...
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...
2 months ago | 0
| accepted
Answered
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 ...
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 ...
2 months ago | 0
Answered
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,...
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,...
2 months ago | 1
Answered
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...
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...
2 months ago | 0
Answered
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...
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...
2 months ago | 1
Answered
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]))...
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]))...
2 months ago | 1
Answered
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 ...
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 ...
2 months ago | 0
Answered
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, ...
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, ...
2 months ago | 0
| accepted
Answered
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...
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...
2 months ago | 0
Answered
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...
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...
2 months ago | 0
| accepted
Answered
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...
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...
2 months ago | 3
