difference between "care" and "lqry"?

I would like to know the differences between matlab function "care" and "lqry".

care needs the matrices A,B,Q,R. lqry needs also C and D. But what are matrices C and D? In the matlab help, "help lqry", they say that

 system dynamics  dx/dt = Ax + Bu,  y = Cx + Du...

but what is y? and C and D?

[Cheetamun Koshal]

y is the output of the dynamic system. C and D are the matrices that will form the output.

There is no big difference in care and lqry except for the lqry the cost function depend on the output and with care the cost function does not depend on the output. So it you want to minimize the cost function wrt to the output , choose the lqry

Answer 1

[Sean de Wolski]

As with any MATLAB function, I highly recommend reading the doc rather than the help. It has more details and examples:

doc lqry