To find a vector subset of a matrix in sequence?

1 回表示 (過去 30 日間)
Vishal Sharma
Vishal Sharma 2017 年 1 月 27 日
コメント済み: Vishal Sharma 2017 年 1 月 27 日
I have a vector A = [1 2 3] And another matrix B = [2 3 4 1; 1 2 3 4; 2 4 1 3; 2 3 1 4]
I want to know which row of vector A is subset of Matrix B (in same sequence of A, i.e. 1 2 3
The answer is 2nd row of B matrix

採用された回答

Thibaut Jacqmin
Thibaut Jacqmin 2017 年 1 月 27 日
Here is a solution in one line :
A = [1 2 3];
B = [2 3 4 1; 1 2 3 4; 2 4 1 3; 2 3 1 4];
% Reshape B in a 1D array (all rows in a line)
C = reshape(B', [1, numel(B)]);
% Then use strfind to find a pattern in a string pattern within a string
linear_index = strfind(C, A);
% Compute the row number of the pattern knowing the initial number of columns
row_number = ceil(linear_index/size(B, 2));
% Or do it in a single line :
row_number = ceil(strfind(reshape(B', [1, numel(B)]), A)/size(B, 2));
  2 件のコメント
Jan
Jan 2017 年 1 月 27 日
A good idea.
The current version fails, if the searched vector appears over the margins:
B = [2 3 4 1; 2 3 1 4]
But you can filter all occurrences, which do not start between 1 and size(B,2)-length(A).
Vishal Sharma
Vishal Sharma 2017 年 1 月 27 日
please suggest code for this case

サインインしてコメントする。

その他の回答 (0 件)

カテゴリ

Help Center および File ExchangeNaNs についてさらに検索

タグ

Community Treasure Hunt

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

Start Hunting!

Translated by