Is there a function that does the same thing as the numel function?

4 次查看（过去 30 天）
E
E 2022-10-21
编辑： John D'Errico 2022-10-21
Hello, I was wondering what other functions could be used to achieve the same result as the numel function?

请先登录，再回答此问题。

采纳的回答

Matt J
Matt J 2022-10-21
编辑：Matt J 2022-10-21
Assuming X is one of the built-in Matlab variable types,
prod(size(X))
or
length(X(:))

更多回答（1 个）

John D'Errico
John D'Errico 2022-10-21
编辑：John D'Errico 2022-10-21
There are multiple ways you COULD achieve the same result as numel. Not all of them are good. For example, length ALMOST does the same thing, as long as you are working with a vector. But length is not the same if the argument is an array. So you could first reshape your array to be a vector, and THEN use length.
Or, you could use size. What would prod(size(X)) tell you about the array X?
For that matter, you could even use sum (in conjunction with some other tools.) Seriously, you could. You don't want to, as it is a crap solution, but it would work. Thus, what would this do:
sum(ones(size(X)),'all')
Heck, even nnz would work, as long as there are no NaNs in the array.
nnz(X | ~X)
Although that would also fail if your array is not numeric, a cell array, for example.
Just use numel.

类别

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

标签

Community Treasure Hunt

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

Start Hunting!

Translated by