check whether a number belongs to an array or not

687 次查看（过去 30 天）
biswajita lenka
biswajita lenka 2011-12-28
评论： Walter Roberson 2018-3-30
hi all, i want to check a number in the array.i have created an array and i want to know that a whether a perticular number belongs to the array or not. is there any inbuild function for "belongs to" in matlab. can anybody help me?

请先登录，再回答此问题。

采纳的回答

Walter Roberson
Walter Roberson 2011-12-28
ismember()
Note: if you are not using purely whole numbers, then please read http://matlab.wikia.com/wiki/FAQ#Why_is_0.3_-_0.2_-_0.1_.28or_similar.29_not_equal_to_zero.3F
  5 个评论
显示 3更早的评论
Walter Roberson
Walter Roberson 2018-3-30
Note: later versions of MATLAB added ismembertol() for dealing with floating point numbers.

请先登录，再进行评论。

更多回答（1 个）

Jan
Jan 2011-12-28
A = floor(rand(100, 100) * 1000);
contains5 = any(A(:) == 5);
If the array is large and the searched element is found early, Matlab wastes a lot of time by searching the rest of the array. Then this C-Mex is faster: FEX: anyEq.
  4 个评论
显示 2更早的评论
ha ha
ha ha 2018-3-30
@Jan. Can you teach me how to run FEX: anyEq. as you mentioned? Thanks
James Tursa
James Tursa 2018-3-30
- Download the code from the provided link
- Compile the code at the command line:
mex anyEq.c -largeArrayDims
- Use the function like any other function. For help on syntax,
help anyEq

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Function Creation 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