How to use Find (or any other function) to create an Array

Hi Everyone,

I have an array, S that appears as so:

And I want to Find the last place where a 1 occured. However, I essentially want to find the last place for each column (I am unsure of how to describe this)

I want my find to be as so:

Intervals = [1 1 1 1 1

3 2

4 ]

With using the max function I would like to create the array:

Max = [4 1 1 1 2]

The rows represent days and columns represent the replication - so essential I want to find the last day the replication achieved a 1.

Any help would be greatly appreciated even a push in the right direction :)

Answer 1

[Ameer Hamza]

Try this

S = [
    1 1 1 1 1
    0 0 0 0 1
    1 0 0 0 0
    1 0 0 0 0
    0 0 0 0 0
    0 0 0 0 0];

[~, idx] = max(flipud(S));
idx = size(S,1)-idx+1;

Result

>> idx
idx =
     4     1     1     1     2

Answer 2

[Alan Stevens]

Here's another possible way

r = repmat((1:9)',1,5); max(r.*S_dash)

[Lucinda Nott]

Thanks Alan - this worked a charm :)