dcgain
Low-frequency (DC) gain of LTI system
Syntax
Description
k = dcgain(sys)
computes the DC gain
k
of the LTI model sys
.
Continuous Time
The continuous-time DC gain is the transfer function value at the frequency s = 0. For state-space models with matrices (A, B, C, D), this value is
K = D – CA–1B (1) Discrete Time
The discrete-time DC gain is the transfer function value at z = 1. For state-space models with matrices (A, B, C, D), this value is
K = D + C(I – A)–1B (2)
Examples
Tips
The DC gain is infinite for systems with integrators.
Version History
Introduced before R2006a