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Double precision: Why does fprintf print "extra" wrong non zero digits?
The "extra" digits that look incorrect to you are simply the result of doing an exact conversion of the actual floating point bi...

9 meses hace | 1

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Respondida
What does MATLAB actually do when switching precisions?
When converting from IEEE single to double, the sign bit is retained, the exponent bits are adjusted to match the same exponent ...

9 meses hace | 2

Respondida
I want to solve ODE for a complex systems in a rk4 method
Just turn all the y( ) stuff into row or column vectors. E.g., suppose we use column vectors, then something like this ... y = ...

9 meses hace | 0

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Respondida
quat2angle / atan2 strange quadrant change when calculating angle
You don't show us your code, but in general I would note that angle changes like this are sometimes the result of whole quaterni...

9 meses hace | 0

Respondida
Active rotation with quaternions: from initial orientation given with Euler angles get the new orientation after an active rotation described by the qr quaternion.
Yes, for your convention q' = q * qr is mathematically correct. But note that this formula only works for certain quaternion co...

9 meses hace | 1

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Pregunta

Conjugate of Symbolic Root doesn't change anything
Reference question first asked here: https://stackoverflow.com/questions/78010011/matlab-bug-with-root-and-conj Basically, the...

9 meses hace | 2 respuestas | 1

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Respondida
sparse matrix entries are not displayed correctly
I finally finished my sparse matrix integrity checker. You can find it in the FEX under the name SAREK (I think you will be able...

10 meses hace | 0

Respondida
the tranpose of transpose doed not equals the original matrix
I finally finished my sparse matrix integrity checker. You can find it in the FEX under the name SAREK (I think you will be able...

10 meses hace | 2

Enviada

SAREK - Sparse Analyzer Real Et Komplex
The SAREK function analyzes a sparse matrix for integrity. Useful especially for checking sparse matrices built by 3rd party s/w...

10 meses hace | 1 descarga |

Respondida
Help with state representation of my 3-mass 2-spring system
The k terms in the equations above appear to be non-linear. Your A matrix doesn't account for the cubic parts.

10 meses hace | 0

Respondida
Calculate angles correctly between two vectors using the dot product.
Also see this related link for a robust method using atan2 that can recover small angles: https://www.mathworks.com/matlabcentr...

11 meses hace | 0

Respondida
How can I make memory persistent between calls to a MEX-file in MATLAB?
So, the accepted answer has bugs. Namely: They don't include the header for memcpy They don't check the input argument properl...

11 meses hace | 0

Respondida
Index in position 1 exceeds array bounds (must not exceed 8).
Here is how to debug these types of errors: Type the following at the command prompt: dbstop if error Then run your code. Whe...

11 meses hace | 0

Respondida
matlab mex in-place editing via "mxUnshareArray" or similar functionality
So, MATLAB has never officially supported modifying input variables in-place in a mex routine. There are potential side effects ...

11 meses hace | 0

Respondida
Static methods are unnecessary, right?
I use Constant Properties and Static Methods all the time in classes I am creating. In particular, when I am developing a group...

12 meses hace | 1

Respondida
Speed of the abs function
Although I applaud your thinking about this problem, this level of optimization is hard to achieve with a language such as MATLA...

12 meses hace | 2

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Respondida
How would I write these in MATLAB
Depends on what those subscripts mean. E.g., maybe this y41 = -(x41^1.5 * cos(x41)^3) + 40; y42 = x42 * sin(x42^2); or this ...

12 meses hace | 0

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Respondida
How to find roots of a quartic function with unknown constant coefficients?
You can look here: https://en.wikipedia.org/wiki/Quartic_function But the nature of the roots is going to depend on the value ...

12 meses hace | 0

Respondida
What calendar system does MATLAB use?
I know this is an old post, but the accepted answer is a bit misleading. MATLAB certainly does use a specific calendar system. ...

alrededor de 1 año hace | 3

Respondida
Rungekuttan for a system of 2 DOE functions
It would be better to have a single state vector for your solution so that you can easily compare your results to MATLAB ode45( ...

alrededor de 1 año hace | 0

Respondida
How much data does an array take?
The data is held in contiguous memory, so yes for a full real double an NxN matrix would take 8*N^2 bytes for the data. Then the...

alrededor de 1 año hace | 0

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Respondida
Multiply matrices in cell array by another matrix
You may be stuck with the loop. There are ways to rearrange and stack things so that you can do everything in a single matrix m...

alrededor de 1 año hace | 0

Respondida
Reading a large binary file
Try data = fread(fd, '*int16'); When you use 'int16' for the type to read, MATLAB reads as int16 and then converts to double (...

alrededor de 1 año hace | 1

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Respondida
Incorrect Dimensions for matrix multiplication
Because you are using matrix operators instead of element-wise operators. Try this: Rtf=(cosh(m.*Lf)+(h./(m.*Kf)).*sinh(m.*Lf))...

alrededor de 1 año hace | 0

Respondida
Why is pow2() slow? Fastest way?
Another way is just to add d to the exponent bits. Probably fastest to do this in a mex routine where edge checking can easily b...

alrededor de 1 año hace | 0

Respondida
Values are getting converted to double automatically.
Here is what I get just displaying the character string. I inserted brackets [ ] for concatenation: ab=[0.5,0.75,1,1.25,1.5,2];...

alrededor de 1 año hace | 2

Respondida
help with parallelization of matrix operations
Both of these operations can be multi-threaded in the background, but this kind of timing test is not straightforward to do beca...

alrededor de 1 año hace | 0

Respondida
Field II kidney example does not work due to "Requested array exceeds the maximum possible variable size." error
At first glance this is the obvious problem in the original source code: The dimensions array needs to be the proper integer si...

alrededor de 1 año hace | 0

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Pregunta

Is there a classdef startup/initializer method?
When a classdef is first loaded into memory (via object instance creation or static method call etc.), is there a way to get a s...

alrededor de 1 año hace | 1 respuesta | 1

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Pregunta

How to update leap seconds
The current version of MATLAB has a function to give you the leap second information that it is using. E.g., [T,vers] = leapsec...

alrededor de 1 año hace | 2 respuestas | 0

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