octave - how to count the row which match a combined condition? -


for example, have matrix m = 

1 0 1 0 1 1; 0 1 0 1 0 1; 1 0 1 0 1 1; 0 1 0 1 0 1

i want count number of row first element m(i, 1) = 1 , third element m(i,3) = 1.

use loop work. but, hope there easy way that. octave function sum seems support 1 condition.

it's pretty easy find rows matching condition in octave:

m(:,1) == 1 # m(i, 1) = 1 m(:,3) == 1 # m(i, 3) = 1

you combine multiple conditions using octave & (logical and) , | (logical or) operators:

(m(:,1) == 1) & (m(:,3) == 1)

if want number of matching roes, use sum function:

sum((m(:,1) == 1) & (m(:,3) == 1))

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