Vectorizing a loop calculation
2 visualizaciones (últimos 30 días)
Mostrar comentarios más antiguos
Hi,
Is it possible to convert the loop below into a vector calculation? Thank you.
dataset=table();
dataset.value=rand(30,1);
dataset.time=sort(rand(30,1));
timefilter=dataset.time-0.2;
result1=repmat(NaN,height(dataset),1);
result2=repmat(NaN,height(dataset),1);
result3=repmat(NaN,height(dataset),1);
%Loop:
for row=5:height(dataset)
startrow=min(find(dataset.time >=timefilter(row)));
result1(row,1)=nansum(dataset.value(startrow:row));
result2(row,1)=length(dataset.value(startrow:row));
result3(row,1)=nanstd(dataset.value(startrow:row)) ;
end
3 comentarios
Meade
el 26 de Feb. de 2018
The sum, length, and std calculations are so trivially fast that it might be fastest to calculate them for the entire array, then just sort. If this doesn't seem unreasonable for your use, I would use bsxfun or arrayfun on your data, then sort. That would be fastest I think.
That would get rid of the loop entirely.
Respuestas (0)
Ver también
Categorías
Más información sobre Loops and Conditional Statements en Help Center y File Exchange.
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!