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Submitted
HPF - a big decimal class
High precision floating point arithmetic, a new class written in MATLAB
18 hours ago | 14 downloads |
Answered
In how many functions using the global variable, can a global variable be declared?
There is no limit on how many functions can use a global variable. At the same time, I will plead, for your own sanity, to recon...
In how many functions using the global variable, can a global variable be declared?
There is no limit on how many functions can use a global variable. At the same time, I will plead, for your own sanity, to recon...
16 days ago | 1
Answered
How do I plot a graph with the grid for trig functions with 0 ≤ x ≤ 2π
@Sean syms x f = cos(x) dfdx = diff(f) help fplot
How do I plot a graph with the grid for trig functions with 0 ≤ x ≤ 2π
@Sean syms x f = cos(x) dfdx = diff(f) help fplot
16 days ago | 0
| accepted
Answered
Should I need keep in my PC previous versions of Matlab?
Some of us keep older releases, just to answer a question about an older release, testing out code in the old release. I do ten...
Should I need keep in my PC previous versions of Matlab?
Some of us keep older releases, just to answer a question about an older release, testing out code in the old release. I do ten...
17 days ago | 0
Answered
Unable to fetch more decimal points for values stored in sldd
You need to learn about the format command. All of the digits are still there, they were just not reported. I'll add a few digit...
Unable to fetch more decimal points for values stored in sldd
You need to learn about the format command. All of the digits are still there, they were just not reported. I'll add a few digit...
27 days ago | 1
Answered
The symbol "1" is not a scalar in integral3
If ALL you want to do is compute a volume, especially of such a simple domain, there are better ways to do so. If the domain is ...
The symbol "1" is not a scalar in integral3
If ALL you want to do is compute a volume, especially of such a simple domain, there are better ways to do so. If the domain is ...
30 days ago | 1
Answered
How does the svd function determine or fix the phase of singular vectors?
First, signs are to some extent arbitrary. That is, for EIG, you can multiply an eigenvector by -1, and it is still an eigenvect...
How does the svd function determine or fix the phase of singular vectors?
First, signs are to some extent arbitrary. That is, for EIG, you can multiply an eigenvector by -1, and it is still an eigenvect...
1 month ago | 1
Answered
Obtaining the differential equations from graphical representation of the problem
Can you show that a set of equations is a valid representation of some data, merely by comparing them to a curve you find in som...
Obtaining the differential equations from graphical representation of the problem
Can you show that a set of equations is a valid representation of some data, merely by comparing them to a curve you find in som...
1 month ago | 0
| accepted
Answered
Will the old-style class definitions be supported in future version of Matlab?
One thing you cannot realistically ask on Answers (if you expect a fully valid answer) is what decisions about MATLAB will be ma...
Will the old-style class definitions be supported in future version of Matlab?
One thing you cannot realistically ask on Answers (if you expect a fully valid answer) is what decisions about MATLAB will be ma...
1 month ago | 1
Answered
Modelling a system of differential equations with recurrences in matlab
This is known as a delay differential equation. You will find any solvers for them starting with the letters dde. help dde23 Y...
Modelling a system of differential equations with recurrences in matlab
This is known as a delay differential equation. You will find any solvers for them starting with the letters dde. help dde23 Y...
1 month ago | 0
Answered
Iterating the eigenvalue function (eig) produces patterns --- is this a well known result?
I'd have a hard time believing this is well known. @Christine Tobler would be the one to know though, and she agrees. It just f...
Iterating the eigenvalue function (eig) produces patterns --- is this a well known result?
I'd have a hard time believing this is well known. @Christine Tobler would be the one to know though, and she agrees. It just f...
1 month ago | 0
Answered
Question on the format of 2D curve fit equations in plot
Scientific notation. 6.588e + 06x^2 == 6.588*10^6 * x^2 Note that it is easier and faster to write, and even a bit easier to ...
Question on the format of 2D curve fit equations in plot
Scientific notation. 6.588e + 06x^2 == 6.588*10^6 * x^2 Note that it is easier and faster to write, and even a bit easier to ...
2 months ago | 0
| accepted
Answered
How do I find the average of a vector of units by using a for loop?
When you create a variable name, NEVER, NEVER, NEVER use a name that is an existing and useful function name. (Well, it might be...
How do I find the average of a vector of units by using a for loop?
When you create a variable name, NEVER, NEVER, NEVER use a name that is an existing and useful function name. (Well, it might be...
2 months ago | 0
Answered
how to find orthonormal vector with condition?
Confusing question. Which probably means I'm misunderstanding your goal here, or that I am myself confused, which is not uncommo...
how to find orthonormal vector with condition?
Confusing question. Which probably means I'm misunderstanding your goal here, or that I am myself confused, which is not uncommo...
2 months ago | 0
Answered
Closed contour with least square differences to dataset
This can be quite difficult if you have some completely arbitrary form. But you tell us this is a simple closed form. And as lon...
Closed contour with least square differences to dataset
This can be quite difficult if you have some completely arbitrary form. But you tell us this is a simple closed form. And as lon...
2 months ago | 0
Answered
MATLAB R2018a needed
We cannot give you a copy of MATLAB. Answers is not customer support anyway. And even they don't just give out copies for anyone...
MATLAB R2018a needed
We cannot give you a copy of MATLAB. Answers is not customer support anyway. And even they don't just give out copies for anyone...
2 months ago | 0
Answered
[coeffA,scoreA,latentA] = pca(X);
The editor likes to complain. Just the kind of program it is. Think about this as a suggestion, a hint, in case maybe your code...
[coeffA,scoreA,latentA] = pca(X);
The editor likes to complain. Just the kind of program it is. Think about this as a suggestion, a hint, in case maybe your code...
2 months ago | 0
Answered
How to define 1-bit variable in data dictionary?
MATLAB does not have a true 1-bit data class. Even a logical, which is clearly a 1 bit thing, thus either true or false, is sto...
How to define 1-bit variable in data dictionary?
MATLAB does not have a true 1-bit data class. Even a logical, which is clearly a 1 bit thing, thus either true or false, is sto...
2 months ago | 0
| accepted
Answered
Polyfit isn't adjusting to decreasing sinoidal data
Do you appreciate just how NON-polynomial-like this data is? Your data appears to be a variation of decaying sinusoid. While, ...
Polyfit isn't adjusting to decreasing sinoidal data
Do you appreciate just how NON-polynomial-like this data is? Your data appears to be a variation of decaying sinusoid. While, ...
2 months ago | 0
| accepted
Answered
Precision Loss in Arithmetic Encoding of Binary Vectors for Reversible Data Hiding in 3D Meshes
You are telling us that you effectively have a binary number with 7000 binary bits. You convert it to a decimal number, and then...
Precision Loss in Arithmetic Encoding of Binary Vectors for Reversible Data Hiding in 3D Meshes
You are telling us that you effectively have a binary number with 7000 binary bits. You convert it to a decimal number, and then...
2 months ago | 0
| accepted
Answered
SVD to a matrix subset (rows)
No, I don't think you can easily find the SVD of a subset of the rows of a matrix, based on the SVD of the full matrix. At least...
SVD to a matrix subset (rows)
No, I don't think you can easily find the SVD of a subset of the rows of a matrix, based on the SVD of the full matrix. At least...
2 months ago | 2
Answered
I can not say wether Eigs is giving expected results or not
It is literally trivial to get large differences there. We need not even use eigs. Eig will suffice. A0 = randn(6); A0 = A0 + A...
I can not say wether Eigs is giving expected results or not
It is literally trivial to get large differences there. We need not even use eigs. Eig will suffice. A0 = randn(6); A0 = A0 + A...
3 months ago | 2
| accepted
Answered
How to correctly find the solution of a system of equations containing trigonometric functions
It was smart of you to look at the results, and question them. Always think about what comes out from a solver. Does the solutio...
How to correctly find the solution of a system of equations containing trigonometric functions
It was smart of you to look at the results, and question them. Always think about what comes out from a solver. Does the solutio...
3 months ago | 0
Answered
Analytic solution of quatric polynomial does not add up
One of the things you need to learn about symbolic algebra, is two expressions may not look the same, but that does not mean the...
Analytic solution of quatric polynomial does not add up
One of the things you need to learn about symbolic algebra, is two expressions may not look the same, but that does not mean the...
3 months ago | 0
Answered
Function requires a Toolbox for which you do not have a license
If you could use it in the past, then you had a license for that toolbox. You cannot use a function from a toolbox where you lac...
Function requires a Toolbox for which you do not have a license
If you could use it in the past, then you had a license for that toolbox. You cannot use a function from a toolbox where you lac...
3 months ago | 0
Answered
save a cmyk image in jpeg
No. Imwrite cannot save a CMYK image to JPG. However, it can save a 4 channel image to a PNG format. Then I would open the image...
save a cmyk image in jpeg
No. Imwrite cannot save a CMYK image to JPG. However, it can save a 4 channel image to a PNG format. Then I would open the image...
3 months ago | 0
| accepted
Answered
Help with Difference Equation in MATLAB
Since V_i and h_i appear to vary with the index i, there is no analytical solution. (If V and h were constants, not changing wit...
Help with Difference Equation in MATLAB
Since V_i and h_i appear to vary with the index i, there is no analytical solution. (If V and h were constants, not changing wit...
3 months ago | 0
Answered
Unexpected results using SVD to separate components that make up a function
Yes. You do misunderstand how svd works, and what it produces. As well, I think you misunderstand what a rank 1 matrix means. A...
Unexpected results using SVD to separate components that make up a function
Yes. You do misunderstand how svd works, and what it produces. As well, I think you misunderstand what a rank 1 matrix means. A...
3 months ago | 1
| accepted
Answered
Why does DC offset occur when integrating AC signals in MATLAB/Simulink?
It looks like you want to integrate what appears to be a sine wave. You did that, expecting to get a pure cosine wave, Right? ...
Why does DC offset occur when integrating AC signals in MATLAB/Simulink?
It looks like you want to integrate what appears to be a sine wave. You did that, expecting to get a pure cosine wave, Right? ...
3 months ago | 2
Answered
fill function sometimes working and sometimes not working, why?
Seems trivial to me. (Ok, easy. Triviality is in the eye of the beholder.) I don't give a hoot about how many real roots it has,...
fill function sometimes working and sometimes not working, why?
Seems trivial to me. (Ok, easy. Triviality is in the eye of the beholder.) I don't give a hoot about how many real roots it has,...
3 months ago | 0
