Feedback connection command explaination

hello, its a command from Kalman filter help example,

SimModel = feedback(sys,1,4,2,1); % Close loop around input #4 and output #2

i want to ask what is the meaning of feedback(sys,1,4,2,1) command? there is conenction of input#4 with output#2, but what are 1's one the both sides of 4 and 2?

Answer 1

[Anish Mitra]

The first 1 is the feedback system (a static gain of 1), and the last 1 is indicating positive feedback.

https://www.mathworks.com/help/control/ref/feedback.html#mw_21da8013-8ed9-4c60-8ad7-1a2691b14ae6

[AR]

thank you