Counting every other number in a list

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Howdy.
I have a matrix
mylist = [1:10]
I need to count every other number in this matrix
I can't use the odd or even distinguishing tests such as...
for i = 1:length(mylist)
if rem(mylist(i),2) ~= 0;
eo_total = eo_total + 1
end
end
Because this only counts the odd numbers in my for loop. So if I had a matrix
mylist(2) = [ 2 4 6 8 10]
eo_total = 0 instead of 2
any ideas?

采纳的回答

the cyclist
the cyclist 2020-9-12
I'm not sure what you mean by "count" them, but the following vector will store every other element from mylist, starting with the first one:
out = mylist(1:2:end)
  2 个评论
Nathaniel Wolff
Nathaniel Wolff 2020-9-12
by count I mean that litterally. I want to count every other other digit in my matrix.
for instance
[1 2 3 4 5]
Ideally i would have a function that would output 2. Becuause if I start at 1, not counting itself, the next other number would be 3 then the last is 5. But I can't have it be odd or even because this list might be something disproportionalty even or odd.
thank you for the code, I can just use a length(out) to count the number of digits in this new matrix.
that's actually much simpler then what I was trying to do with for loops
the cyclist
the cyclist 2020-9-12
Oh. Then it's probably more efficient to do
ceil(numel(mylist)/2)
Then you don't need to create a second vector.

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