What does this statement mean in matlab?
for i = n:-1:j
It's the header of a for loop. i takes on the value of n initially; the loop body (which you haven't shown) is executed; i changes by -1; and the loop repeats until i and j are equal.
Refer to: http://www.mathworks.com/access/helpdesk_r13/help/toolbox/rptgen/forloop.html
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