Improving performance of interp1 function inside for loop

2 次查看（过去 30 天）
Arya
Arya 2016-8-23
编辑： Arya 2016-8-24
Hello,
I'm looking for some insight on troubleshooting a matlab fcn bottleneck in a Simulink project. According to the code profiler this Matlab in-line function is (understandably) hogging the runtime:
function [preview,preview_a] = fcn(dp,X_matrix,rho_matrix)
%preallocate
rho_matrix_t = rho_matrix'
preview_a=zeros(1,185);
for i=1:dp
preview(i)=X+i;
preview_a(i)=interp1(X_matrix,rho_matrix_t,preview(i));
end
I understand the interp1 will inevitably consume some CPU time, but could there be some approach to improve the above code?
In the meantime I have these following in mind:
  1. Vectorization: building preview(1:dp) then do interp1 operation in batch (but I suspect interp1 doesn't support this)
  2. Using other built-in Simulink block that does equivalent jobs? (I've been looking at interp block, will see if it does the job).
Any suggestions are welcomed. :)
Regards,
Arya

请先登录，再回答此问题。

采纳的回答

Walter Roberson
Walter Roberson 2016-8-23
interp1() is fine with accepting a vector of points to interpolate at. Building preview ahead of time should work well.
  1 个评论
Arya
Arya 2016-8-24
编辑：Arya 2016-8-24
Indeed, it turns out interp1() is happy to accept vector points, this is what I did:
function [preview,preview_a] = fcn(dp,X_matrix,rho_matrix)
%preallocate
rho_matrix_t = rho_matrix'
preview_a=zeros(1,185);
i=1:dp
preview(i) = X+i
preview_a(i)=interp1(X_matrix,rho_matrix_t,preview(i));
Much simpler than I thought, and seem to accelerate the execution time a bit.
Cheers!

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Simulink 的更多信息

标签

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by