Double integral over array
2 ビュー (過去 30 日間)
古いコメントを表示
Hi,
Evaluating a double integral over a large number of pixels takes an hour, even with the parallel toolbox. I can't figure out how to vectoirze this calculation to speed it up...suggestions welcome!
parfor iRow = 1:nRows
for iCol = 1:nCols
X = pitch_mm * (iRow - nRows/2 - 0.5);
Y = pitch_mm * (iCol - nCols/2 - 0.5);
% projected solid angle differential
dOmega = @(Xap,Yap) (apDist_mm ./ ((apDist_mm)^2 + (X-Xap).^2 + (Y-Yap).^2)).^2;
% convert to polar & integrate
dOmegaPolar = @(theta,r) dOmega(r.*cos(theta),r.*sin(theta)).*r;
cos4(iRow,iCol) = integral2(dOmegaPolar,0,2*pi,0,apDiam_mm/2);
end
end
0 件のコメント
回答 (1 件)
David Hill
2020 年 2 月 1 日
X=pitch_mm*([1:nRows]-nRows/2-.5);
Y=pitch_mm*([1:nCols]-nCols/2-.5);
dOmegaPolar = @(theta,r) dOmega(r.*cos(theta),r.*sin(theta)).*r;
dOmega = @(Xap,Yap) (apDist_mm ./ ((apDist_mm)^2 + (x-Xap).^2 + (y-Yap).^2)).^2;
cos4=zeros(nRows,nCols);%preallocate
parfor iRow = 1:nRows
x=X(iRow);
for iCol = 1:nCols
y=Y(iCol);
cos4(iRow,iCol) = integral2(dOmegaPolar,0,2*pi,0,apDiam_mm/2);
end
end
Above should speed things up some.
2 件のコメント
David Hill
2020 年 2 月 1 日
X=pitch_mm*([1:nRows]-nRows/2-.5);
Y=pitch_mm*([1:nCols]-nCols/2-.5);
dOmegaPolar = @(theta,r) dOmega(r.*cos(theta),r.*sin(theta)).*r;
cos4=zeros(nRows,nCols);%preallocate
parfor iRow = 1:nRows
for iCol = 1:nCols
dOmega = @(Xap,Yap) (apDist_mm ./ ((apDist_mm)^2 + (X(iRow)-Xap).^2 + (Y(iCol)-Yap).^2)).^2;%this needs to move inside loop
cos4(iRow,iCol) = integral2(dOmegaPolar,0,2*pi,0,apDiam_mm/2);
end
end
参考
カテゴリ
Help Center および File Exchange で Logical についてさらに検索
製品
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!