What is difference between "Direct form" and "Normal Direct form"? What is difference between &quot;Direct form&quot; and &quot;Normal Direct form&quot;?
I was reading about filters implementations(structures) and found out both words &quot;direct form&quot;and &quot;normal direct form&quot; especially in proakis,2nd edition as shown highlighted in attached snapshot
The modifier normal is meant to distinguish the form from the transposed form. So there is a normal direct form I, a transposed direct form I, and similarly for the direct form II. As far as I know, this terminology is not universal, and I've only come across it in books (co-)written by Manolakis or Ingle.