What is this line of code doing?

blob(blob == blob(i,j-1)) = blob(i-1,j);

Answer 1

[Ronit]

Hello Quazi,

blob(blob == blob(i,j-1)) = blob(i-1,j);

This line is replacing all occurrences of the value blob(i, j-1) in the matrix blob with the value at blob(i-1, j). To understand this in detail, let us go through this step by step:

1. blob(i, j-1): This accesses the element in the blob matrix located at row i and column j-1.
2. blob == blob(i, j-1): This creates a logical matrix of the same size as blob, where each element is true if it is equal to blob(i, j-1) and false otherwise.
3. blob(blob == blob(i, j-1)): This uses logical indexing to select all elements in blob that are equal to blob(i, j-1).
4. blob(i-1, j): This accesses the element in the blob matrix located at row i-1 and column j.
5. The final operation assigns the value of blob(i-1, j) to all elements in blob that are equal to blob(i, j-1).

I hope this explains everything!