To find a vector subset of a matrix in sequence?

3 visualizaciones (últimos 30 días)
Vishal Sharma
Vishal Sharma el 27 de En. de 2017
Comentada: Vishal Sharma el 27 de En. de 2017
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

Respuesta aceptada

Thibaut Jacqmin
Thibaut Jacqmin el 27 de En. de 2017
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 comentarios
Jan
Jan el 27 de En. de 2017
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 el 27 de En. de 2017
please suggest code for this case

Iniciar sesión para comentar.

Más respuestas (0)

Categorías

Más información sobre Characters and Strings en Help Center y File Exchange.

Etiquetas

Community Treasure Hunt

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

Start Hunting!

Translated by