How do I count how many times in a row a value occurs?

6 visualizaciones (últimos 30 días)
David Haydock
David Haydock el 17 de Mayo de 2022
Editada: Torsten el 17 de Mayo de 2022
If I have some list, say:
A = [1 2 4 3 1 1 1 1];
How do I calculate and store *how many times in a row* each number occurs?
For example, for the value 1, I would want an output of [1, 4], since it appears one time, then when it appears again in the list it repeats four times.
Any help would be appreciated.

Respuesta aceptada

Monica Roberts
Monica Roberts el 17 de Mayo de 2022
Probably not the fastest/cleanest but this should work. Assuming that A contains at least one value.
ind = find(A==1);
answer = [];
count = 1;
for i = 1:numel(ind)-1
d = ind(i+1)-ind(i);
if d == 1
count = count+1;
answer = [answer,count];
count = 1;
answer = [answer,count];

Más respuestas (1)

Torsten el 17 de Mayo de 2022
Editada: Torsten el 17 de Mayo de 2022
A = [1 2 4 3 1 1 1 1];
Au = unique(A);
count = arrayfun(@(i)numel(find(A==Au(i))),1:numel(Au))
output = [Au;count].'
Your question is unclear since the 1 appears 5 times in the row. If you want the maximum number of subsequent repetitions of a number or something similar, you should again formulate your question properly.


Más información sobre Resizing and Reshaping Matrices en Help Center y File Exchange.

Community Treasure Hunt

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

Start Hunting!

Translated by