extracting values from a matrix or vector
435 ビュー (過去 30 日間)
古いコメントを表示
Hi!
I'm new at this and a need a litle help.
How can extract non-consecutive numbers from a vector?
For example, a = [11 22 33 44 55]
I want to extract only the 22 and the 55, b = a (...?...)
thanks
0 件のコメント
採用された回答
その他の回答 (1 件)
Image Analyst
2021 年 2 月 17 日
Consecutive in what way? Consecutive in value or index location? None of those numbers are consecutive in their values. Why those two that you chose? What criteria are you using to decide upon the second and fifth indexes?
% To extract odd numbered indexes:
b = a(1 : 2 : end);
% To extract even numbered indexes:
b = a(2 : 2 : end);
In general you can give "a" a vector of actual indexes, like [2, 4, 5] (this is called linear indexing) OR you can give a vector of logicals (or doubles that can be evaluated as logicals) that is the same size as the array, like [false, true, false, true, true] or [0, 1, 0, 1, 1].
2 件のコメント
Image Analyst
2021 年 2 月 17 日
This (indexing and extraction) will be covered in the basic course:
参考
カテゴリ
Help Center および File Exchange で Logical についてさらに検索
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!