finding 3 consecutive negative numbers

I need to find how many times 3 consecutive negative numbers are in the matrix

A = randi([-4,4], n, n)

where n>2 and n<10.

[John D'Errico]

Is this homework?

Is this a question of expected value? I.e., the EXPECTED number of such occurrences, or the actual number of these events for a given matrix?

If it is simply a question of counting those events for a given matrix, then learn to use diff to identify when three numbers are consecutive, as well as a test on the entire array to indicate the negative numbers.

[Image Analyst]

That's a 2D array. Do you want consecutive in both columns and rows?

Hints: Process a row or column at a time. Then threshold, then use regionprops and look for blobs with an area of exactly 3.