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isct, isdt

11-104

11isct, isdt

Purpose Determine whether an LTI model is continuous or discrete

Syntax boo = isct(sys)

boo = isdt(sys)

Description boo = isct(sys) returns 1 (true) if the LTI model sys is continuous and 0

(false) o therw is e. sys is continuous if its sample time is zero, that is, sys.Ts=0.

boo = isdt(sys) returns 1 (true) if sys is dis cret e and 0 (false) otherwise.

Discrete-timeLTImodelshaveanonzerosampletime,exceptforemptymodels

and static gains, which are regarded as eit her continuous or discrete as long as

their sample time is not explicitly set to a nonze ro value. Thus bo th

isct(tf(10))

isdt(tf(10))

are true. H o we ver, if yo u e x plicitl y label a gain as discret e , f or e xamp le , by

typing

g = tf(10,'ts',0.01)

isct(g)

now returns false and only isdt(g) is true.