For this sample matrix:
>> matrix = [cumsum(10*rand(25,1)), rand(25,1) < 0.1]
matrix =
2.6774 0
3.9889 0
10.7113 0
13.0342 0
13.4335 0
13.8455 0
23.4376 0
27.3937 0
33.0231 0
33.0414 0
33.1545 0
35.4013 0
45.2526 0
48.8322 0
49.7725 0
56.3409 1.0000
64.5214 0
66.0233 0
74.9418 0
80.0405 0
87.4213 0
92.1971 0
96.8440 1.0000
106.2857 0
107.8732 0
The following works:
>> t0 = matrix(find(matrix(:,2),1),1)
t0 =
56.3409
