rank question

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1

  1. Isn’t rank of an atom 0, a simple list 1 and “2 3 #til 6” 2. 

  2. in x?y the rank of y should be 1 less than x (I call it the rank rule). 

  3. I believe I have identified the x and y in the following statement correctly as x being “2 3” and y being “2 3#til6” because the webpage says “If there is no match the result is the count of the left argument” . Hence the output of 2 highlighted proves left side is x and right side is y

q)2 3?2 3#til 6

2 2 0

1 2 2

Given this I have following questions

A. Why is 2 3 claimed to be of 0 rank and (0 1 2;4 5) of 1 rank

B. Isn’t the common argument in both expressions (rhs) supposed to be of 1 rank less 

? is rank sensitive; x?y can’t deal with mixed rank x. If rank x is n then x?y looks for objects of rank n-1. e.g.

2 3?2 3#til 6 / looks for rank 0 objects(0 1 2;4 5)?2 3#til 6 / looks for rank 1 objects