- fixed point code can take longer than floating point (but fixed point can be used on devices that have no floating point unit)
- code that does calculations on sufficiently large arrays often ends up calling multithreaded high-performance libraries that use all of the cores. Generated C/C++ code does not call those libraries and so operates single-core. You can use https://www.mathworks.com/help/matlab/ref/maxnumcompthreads.html to test to see if this is the reason the generated code is slower (that is, by restricting your MATLAB to one thread.)
some questions about matlab coder
2 次查看(过去 30 天)
显示 更早的评论
Hi
I am doing my senior project on 5G simulations in matlab. We are doing the QAM using precoder and some modulation functions. We want to convert the code we have into C or C++. We used the matlabe code gen and we converted to C. We were surprised by how slow the C code is compared to matlab. It takes 260 sec for C to run one trial while only 90 sec on matlab. One of the thing we did is set the code gen to use dynamic allocation instead of static. I am looking for some recommendation or suggestions on how to produce a fast enough C code. Is that possible or we have to write the code fro scratch. Thanks
3 个评论
Ryan Livingston
2018-4-27
编辑:Ryan Livingston
2018-4-27
MATLAB Coder added the ability for the generated code to call LAPACK in R2016a:
and FFTW in R2017b:
Using these will give you optimized linear algebra and FFT routines respectively.
回答(3 个)
Ji Lee
2018-4-25
Reducing the usage of dynamic memory allocation is one of the general optimization strategies one can start with when trying to improve the performance of generated code. We do have a useful documentation section that describes various optimizations and patterns. I've linked it below. Included in the first several topics linked from this section is a discussion on variable sizing and dynamic memory allocations.
0 个评论
另请参阅
产品
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!