Community Profile

photo

James Lebak

Last seen: 2 days ago Active since 2012

Statistics

  • Knowledgeable Level 3
  • Revival Level 1
  • 3 Month Streak
  • Knowledgeable Level 2
  • First Answer

View badges

Content Feed

View by

Answered
Why do I receive a warning about a value indexed with no subscripts?
This warning was removed in R2023a. More details are in the release notes.

2 days ago | 0

Answered
Unexpected slowdown using () indexing
Paren-reference in many cases creates a copy. This is expected behavior. NULL(1) is nearly as fast as NULL on a scalar because...

1 year ago | 3

Answered
Overloading subsref and calling the builtin from within causes the class to only return the first value when called on a nested vector of objects.
To get the behavior you want, your class needs to overload numArgumentsFromSubscript. One example implementation of this method ...

1 year ago | 0

| accepted

Answered
Can I use Matlab's default implementation of empty with matlab.mixin.indexing.RedefinesParen?
You do have to provide an 'empty' for your class that inherits from RedefinesParen. Such classes are scalars masquerading as arr...

2 years ago | 0

Answered
Is it a good idea to overload subsref to mimic MATLAB's griddedInterpolant behavior?
Subsref is the way that griddedInterpolant does this. Another way is to inherit from matlab.mixin.indexing.RedefinesParen, or fr...

2 years ago | 1

| accepted

Answered
How to overload a single parentheses indexing operation, not all of them?
I would not do this by overloading indexing. As you point out, overloading indexing is difficult, and as Walter points out you s...

2 years ago | 0

Answered
Wrong varargin when calling memoized functions saved in a handle class as constant properties
This is a bug. I see this behavior in R2020b and earlier, but not in R2021a or R2021b. If you can try either of those more recen...

2 years ago | 0

| accepted

Answered
Matlab 2021b quit when starting Simulink
Looking at the stack, it might be Bug Number2599486: Crash with CreateSharedDataCopy on top of the stack.

2 years ago | 1

| accepted

Answered
Overriding subsref and subsasgn - effect on private properties
Beginning in MATLAB R2021b it is possible to overload parentheses, dot, and brace indexing independently. This gives the ability...

2 years ago | 1

| accepted

Answered
How can I avoid this error when creating a MEX file? "Error: Link of 'mexGPUexample.mex64' failed."
Hi Edward, You stated you were using CUDA 5.5 and VS 2012. When you build MEX files for the GPU, you must use the same versio...

10 years ago | 3

| accepted

Answered
gpuDevice command very slow
MATLAB R2012a doesn't include code for the Kepler series GPUs. This means that the very first time you call any GPU command afte...

11 years ago | 3

| accepted

Answered
BLAS or LAPACK in CUDA kernel
You're correct that you can't call DGETRS and SGETRS directly, as that's CPU-side code. The CUDA 5 version of CUBLAS has a batch...

11 years ago | 0

| accepted

Answered
making the cuda volume renderer included in the sdk work with matlab
Yes, you can use these in a GPU MEX file in R2013a. You will have to compile the MEX file for the GPU as detailed in the <http:/...

11 years ago | 2

| accepted

Answered
"MATLAB was unable to initialize the GPU FFT library" ??
You are correct that the symptoms you mention indicate a memory problem. The GPU FFT requires memory not only for the input and ...

11 years ago | 0

| accepted

Answered
IFFT slow down with using gpuArray
The GeForce GT630M is a mobile graphics card. Frequently, these cards don't perform as well in double-precision as they do in si...

11 years ago | 1

Answered
mex CUDA code to calculate Coulomb field
Mike, I'm glad to hear that you're using the GPU MEX API. Below are my answers to your questions, which you can accept or re...

11 years ago | 0

Answered
two - loop with GPU
Yes, 1:gpuArray(N) for scalar N doesn't work in MATLAB R2013a. Try the following: x=gpuArray.colon(1,N)*ds-L/2; y=gpuArr...

11 years ago | 0

Answered
Help Choosing a GPU?
Obviously, it's going to depend on your problem, but the amount of memory on the card is a very important consideration. Estimat...

11 years ago | 0

Answered
Using multiple GPUs in a parfor type of loop
In R2012b and later, in a matlabpool on a single machine with two GPUs, each worker will use a different GPU by default. You can...

11 years ago | 1

Answered
gather takes really long after using ptx file /CUDA
In MATLAB R2012a and later, GPU functions execute asynchronously in MATLAB. To get accurate timings, you need to call the wait f...

11 years ago | 1

Answered
MATLAB Parallel Computing Toolbox + (2) NVIDIA GeForce GTX 690's in SLI
As far as I can tell, this is not possible, because SLI and CUDA don't interact. The CUDA C Programming Guide makes little menti...

11 years ago | 0

| accepted

Answered
What is the best way to determine if a usable GPU is available?
Hi Joe, There is not presently a function called 'canUseGPU' in Parallel Computing Toolbox. Matt's answer will work. You coul...

11 years ago | 2

Answered
Allocate page locked memory for output array in mex?
Justin, Unfortunately this isn't possible in MATLAB today. The function mxCreateDoubleMatrix returns an mxArray, not a raw po...

12 years ago | 0

| accepted