Calculating Average Duration/Length in an Array

Hello,

I have an array that contains 1 2 3 which each represents a state i.e) 1=sunny day 2=rainy day 3=cloudy day. The array is about 1 million length.

Example: [3 3 3 1 1 1 1 2 1 1 2 3 3]

I would like to figure out the average duration of each state. For state 1, it would be (4+2/2)= 3 days. For state 2, it would be (1+1/2=)1day. And state 3 it would be (3+2/2)=2.5days

I'm wondering if anyone has any suggestion or tips on how to do this with minimal code.

Cheers, David

Answer 1

[Star Strider]

The histc function (with help from unique) is probably the easiest option:

W =  [3 3 3 1 1 1 1 2 1 1 2 3 3];
bins = unique(W);
k = histc(W,bins);
avg = k./2;

[David]

Thanks, I got it all figured out now. Your advice and http://www.mathworks.com/matlabcentral/newsreader/view_thread/331664 helped me do it

[Star Strider]

My pleasure!

I thought you might want to find out the number of repeated sequences next, but I opted to wait and find out. I’m glad you found an applicable solution to the repeated-sequence problem.