Beantwortet
Why does my one calculation take so much longer than the other when its the same function?
When |end| at the end of a function shows a significant amount time the cause is most often the overhead involved in cleaning up...

mehr als 8 Jahre vor | 0

Beantwortet
passing arguments in classdef
This "feature" is undocumented behavior and I would consider it a bug subject to change in the future. All recent versions of ...

mehr als 8 Jahre vor | 1

| akzeptiert

Beantwortet
Calling C/C++ libraries (with associated cstring pointers) in MATLAB
You can only call functions that appear int the output of |libfunctions -full| with arguments that can be converted to those lis...

mehr als 8 Jahre vor | 1

| akzeptiert

Beantwortet
Create prototypes to wrap agains C-Interface DLL - How universal ist the pcwin64.dll created?
The shipping the generated prototype file and compiled thunk file is the recommenced way to distribute code that uses loadlibrar...

mehr als 8 Jahre vor | 0

Beantwortet
Maximum recursion limit of 500 reached
Is sdpvar a class and does it have a reshape method? If so it is getting called in a way that is causing it to call itself inf...

mehr als 8 Jahre vor | 0

Beantwortet
My Student Version of MATLAB cant invert 20x20 matrices or "\" 100x100 matrices
Check out this answer http://www.mathworks.com/matlabcentral/answers/138692-matrix-multiply-crashes-matlab-2014a-on-a-amd-a6-145...

mehr als 8 Jahre vor | 1

Beantwortet
I wrote 2 snippets as below, they both try to find minimum value, but one repetitively uses function handles and the other uses a sub function. It turns out the speed are very different? Why?
Profile your code, think about what the code is doing. Method2 makes one function call to subfun per iteration. Method1 makes...

mehr als 8 Jahre vor | 0

Beantwortet
Dual Xeon and Matlab R2015b - different behaviour on physical vs virtual machine
MATLAB attempts to detect hyper-threading and may choose not use it. We have found that, for the well optimized math libraries,...

mehr als 8 Jahre vor | 2

Beantwortet
Error "Matrix index is out of range for deletion" with dynamic variable names but not hardcoded names?
The code blocks are not doing the same thing. Your loop is doing: uniquefields.('L')('removeL') = [] It could be fixe...

mehr als 8 Jahre vor | 0

| akzeptiert

Beantwortet
calllib issue , change DMA buffer value
Try: pointer.value(:)=pattern2; Assigning directly to |pointer.value| is the same as |buffer=pattern2| in c which repla...

mehr als 8 Jahre vor | 0

| akzeptiert

Beantwortet
Why is my MATLAB R2015b installation 56GB in size?
How is the card formatted? What is the output of chkdsk on the card? If the card is formatted fat32 or exFAT (default for SD...

mehr als 8 Jahre vor | 2

| akzeptiert

Beantwortet
Can Windows version of Matlab be made to generate crash report without human intervention?
There is no documented way to do this in R2015b. I suggest you make a formal request for this feature to support.

mehr als 8 Jahre vor | 0

| akzeptiert

Beantwortet
unloadlibrary still keeps the library loaded!
The problem most is most likely with your library not with MATLAB. When a library is loaded the operating system increases the ...

fast 9 Jahre vor | 0

Beantwortet
"Reshaping" matrix
Simpler and faster solution get rid of the outer loop: xgrid3=NaN(A,D,B); tic for j=1:B xgrid3(:,:,j)=xgrid(P_ind(:...

fast 9 Jahre vor | 0

| akzeptiert

Beantwortet
How to get find() results as a matrix?
How about: [ind(:,1),ind(:,2)]=find(I);

fast 9 Jahre vor | 1

Beantwortet
What can be done to reduce memory usage in MATLAB R2015b?
Do you use/run code that is really data? For instance does some function generate MATLAB code files dynamically that are later ...

fast 9 Jahre vor | 0

Beantwortet
"depth" of mexMakeArrayPersistent ?
mexMakeArrayPersistent should only be called on the top level cell array or structure. When an mxArray is placed in a cell or f...

fast 9 Jahre vor | 1

Beantwortet
Array of stuctures for repeated use in DLL
This should not make any difference but you might try this code instead. ... structs1 = libstruct('my_struct', tmp); ...

fast 9 Jahre vor | 0

Beantwortet
Does loadlibrary function loads all the functions in one dll?
Yes, by default loadlibrary will load all functions found in the header file used to load or create the prototype file. The fu...

fast 9 Jahre vor | 2

| akzeptiert

Beantwortet
Why cant i loadlibrary with relative paths
Loadlibrary runs from a freshly created temporary directory so relative paths will not work as include paths. To build an inc...

fast 9 Jahre vor | 0

| akzeptiert

Beantwortet
Order of magnitude (10 times greater) execution time resulting from order of computations in a script file that are otherwise identical.
This appears to be a bug/limitation in the 64 bit JIT in MATLAB versions prior to R2015b. Other versions of MATLAB don't show t...

fast 9 Jahre vor | 2

Beantwortet
usage of calllib, libpointer, and libstruct with DLL that returns memory
You should be able to do what you are trying to do but have a bug or design flaw. It is best to keep all memory in a single s...

fast 9 Jahre vor | 1

| akzeptiert

Beantwortet
H5L.iterate exception and behavior of native matlab functions() method
I do not know why H5L.iterate needs function handles with a file defined. I suggest you file an enhancement request to remove t...

fast 9 Jahre vor | 0

| akzeptiert

Beantwortet
clear persistent variables in sub-functions
I would not use a perstent variable for this. Use a nested function and local variable function temp = MyMainFunction() ...

fast 9 Jahre vor | 1

Beantwortet
MATLAB's R2015b new JIT experiences a severe degradation in speed in the following example, but the documentation says it was significantly improved. Why would the following simple code run so much slower?
The old (PreR2015b) JIT was highly optimized for a few simple code situations and fell back to the interpreter when it could do ...

fast 9 Jahre vor | 3

| akzeptiert

Beantwortet
load a mtalb compiled dll in matlb
You can't, Loading a MATLAB compiled application directly into MATLAB is deliberately prevented. Quote from loadlibrary limi...

etwa 9 Jahre vor | 0

| akzeptiert

Beantwortet
/D_CRT_SECURE_NO_DEPRECATE /D_SCL_SECURE_NO_DEPRECATE /D_SECURE_SCL=0 >>>>>>>when loading dll
extern "C" { Is c++ not c code. Loadlibrary is only compatible with c headers. Most likely this header can be fixed to be...

etwa 9 Jahre vor | 0

Beantwortet
specify compiler used by loadlibrary
The compiler used is the one configured/found with mex -setup. This answer may help if you need to modify your configuration: <...

etwa 9 Jahre vor | 0

Beantwortet
Assistance trying to load 3rd party dll/headers into Matlab
Only use addheader when a function you want does not appear in libfunctions or the prototype file. Find the header containing t...

etwa 9 Jahre vor | 0

Beantwortet
Error using calllib Too many inputs passed to SimpleFunctionThunk.
Calltype of 'cdecl' is not supported on 64 bit systems however it does work for simple functions with a *limited* number of inte...

etwa 9 Jahre vor | 0