what is wrong with this simple code?

Hi I am trying to create an empty array so that I can add elements to it concatenating them. This avoid the large time it takes if you dont give it a size previous the for loop, as it has to change its size at every iteration. This is the code:

>> days=double.empty(100000,1,0); m=size(days); m

for k=2:numel(UntitledCase_Temp)

days(k)=(UntitledTime(k)-UntitledTime(k-1))/24*3600+days(k-1);

end;

m =

      100000           1           0

??? Attempted to access days(1); index out of bounds because numel(days)=0.

Answer 1

[the cyclist]

Preallocate like this instead

days = zeros(100000,1);