Community Profile

photo

wei zhang


USTC

Last seen: 4 months ago Active since 2016

PHD candidate in life science department

Statistics

All
  • Revival Level 1
  • Promoter
  • Solver
  • Thankful Level 3
  • First Review

View badges

Content Feed

View by

Question


Why identifier "mxGetUint64s" is undefined in mex or cudamex?
Hi, I am trying to deal with unsigned long format arrays in mex. I found in mxGetUint64s page that I should use mxGetUint64s ins...

5 months ago | 1 answer | 1

1

answer

Answered
How could I compile with cuda/thrust library in cudamex?
The example could run well since 2021a.

5 months ago | 0

| accepted

Answered
Why `gpucoder.profile` example failed?
I should thank Matlab team first, especially Hu Halley and Erik. It is all about cupti library including as below. setenv('PATH...

6 months ago | 0

| accepted

Solved


Times 2 - START HERE
Try out this test problem first. Given the variable x as your input, multiply it by two and put the result in y. Examples:...

6 months ago

Question


Why `gpucoder.profile` example failed?
I am trying to profile the gpu code. At first, I tried the example in gpucoder.profile. But it always gives an error with someth...

6 months ago | 1 answer | 0

1

answer

Question


Could matlab use `nvprof` in cuda profiling?
I am using cudamex. I need to profile the time consuming. Is there any sample called "nvprof" with a ".m" file? Or could I use i...

7 months ago | 1 answer | 0

1

answer

Question


Is there a data size limited in the mex of cell format?
I am trying to pass some large cell arrays from mex to Matlab. I found it may stuck Matlab if the output cell array is large. Is...

9 months ago | 0 answers | 0

0

answers

Question


Why `mxGetField` could not be assigned to output of c mex?
I am learning to compile mex with struct. I found a confusing problem. When I use mxGetField to assign the output of my mex, the...

9 months ago | 2 answers | 0

2

answers

Question


How could I compile with cuda/thrust library in cudamex?
Hi, I am trying to build a mex with thrust library with the below code. I got an error. C:\Program Files\MATLAB\R2020b\extern\i...

10 months ago | 1 answer | 0

1

answer

Question


Why `sparse` function accumulate large sparse COO format matrix by index so fast?
Hi, I am dealing with "repeated COO format" sparse matrix. I try to "accumulate" it by its index efficiently. I am inspired by t...

10 months ago | 1 answer | 0

1

answer

Question


Could I pass a 'triangulation' class into mex?
Hi, I am trying to use mexcuda to accelerate some code with triangle mesh. I would like to use 'triangulation' class variable a...

10 months ago | 2 answers | 0

2

answers

Question


How to "free" or "destroy" pointer array of mxArray?
Hi, I am using mexCallMATLAB in mex. So I need to construct pointer array for multi input or output. Like the below tmp variabl...

10 months ago | 1 answer | 0

1

answer

Question


How to set all one gpuArray in mex?
Hi, I need to set a all-one double gpuArray. I think I could use mxGPUCreateGPUArray to initial it. But it seems mxGPUCreateGP...

10 months ago | 1 answer | 0

1

answer

Question


How to make two mxArray* scalar multiply each other?
Hi, I have a simple step of multiplying two double scalar variables in mex. Why not the type "mxDouble" support multiply? Must ...

10 months ago | 1 answer | 0

1

answer

Question


How to check the Bytes of gpuArray?
Hi, I am confusing in checking the Bytes of gpuArrays. It seems every varaible's Bytes is 4. Could I do something more to set ...

10 months ago | 2 answers | 0

2

answers

Question


How to change the class of mxArray double to int in c mex ?
Hi, I am trying to convert a double class mxArray to int. I don't know how to do that. My c code is like below. I would like t...

10 months ago | 0 answers | 0

0

answers

Question


Why built-in conjugated gradient solver for sparse linear matrix runs much faster than normal script, no matter GPU or CPU?
I am trying to profile the conjugated gradient method for Ax = b. A is a large sparse matrix. The conjugated gradient method cou...

10 months ago | 0 answers | 0

0

answers

Question


Could I use double precision with `cusparse` or `cublas` function in mexcuda.cu file?
Hi, I am trying to compile my .cu file with cudamex. In this file, I would like to write some functions in cusparse or cublas f...

10 months ago | 0 answers | 0

0

answers

Question


Could I use the `mxGPUArray` format data in the cuda kernel function?
I am new in compiling the mexcuda. I am trying to use the mxGPUArray as inputs of cuda kernel. My sample.cu code is as below. It...

11 months ago | 1 answer | 0

1

answer

Question


How `gpuArray` save sparse matrix when running Preconditioned conjugated gradient?
Hi, I am using cuda in Matlab to accelerate the Preconditioned conjugated gradient evaluation of "Ax = b". I'm glad to find the ...

11 months ago | 1 answer | 0

1

answer

Question


Is there any function like "specgraphhelper" existing in the 2019a or later version?
I had used a scripted named "select3d", which function is to select points in 3d figure. But when I update my Matlab to 2019a. T...

1 year ago | 0 answers | 0

0

answers

Question


Is there any method to accelerate many small matrix and vector's "mldivide" (4*4)?
I am trying to solve many(4000000) mldivide evaluation. All of them are in the form of "x = A\b". A is a 4*4 matrix, and b is 4*...

1 year ago | 3 answers | 0

3

answers

Answered
How to set the constraints of L0- norm in linear programming?
I found an answer to my own question. I transfer the problem to MILP problem. The idea is from stackExchange. If I make anythi...

1 year ago | 0

Question


How to set the constraints of L0- norm in linear programming?
(sorry, I miss the objective function before. I have edited it well) I am trying to set the L0-norm constraints, which give a c...

1 year ago | 3 answers | 0

3

answers

Question


How to set the sum of the absolute value of variables as inequality matrix and vector in linear programming?
I am trying to solve a linear program with command "linprog". The inequality constrains has a sum of varaibles. e.g. I have 3 va...

1 year ago | 1 answer | 0

1

answer

Question


Is there a way to get the max memory used when I run my script?
I am trying to solve a distributed large sparse linear equation. I found the size of the RAM is the limitation of my algorithm. ...

1 year ago | 1 answer | 0

1

answer

Question


What is the cause of the error of "CPARDISO encountered an error in phase 22: Error code = -2."?
I am trying to solve a large sparse matrix equation Ax = b. A is in 700000*700000, and b is in 700000*500. I am using the distri...

1 year ago | 1 answer | 0

1

answer

Question


Is there any way to accelerate the solving of a series of large sparse positive definite linear equations "Ax=b" with same "A" and different "b"?
I am trying to solve a series of the linear equations Ax=b. A is a large sparse positive definite matrix, in n*n. And b is a vec...

1 year ago | 3 answers | 0

3

answers

Question


Is there any method to calculate the inverse of matrix which changed a few values?
I have a large sparse matrix A and have gotten its inverse matrix inv(A) . Then I need to change an element value to get a new m...

1 year ago | 3 answers | 0

3

answers

Question


Is there any way to speed up the function `changem`?
I am doing some substitutions of the index of triangle mesh. After removing or selecting some points on the mesh, I need to "ret...

1 year ago | 2 answers | 0

2

answers

Load more