I am trying to plot transfer functions and find their resonance frequency and bandwidthy. Apart with me being weak in Matlab knowledge, I kinda know how to do the programming because of examples on the internet and book. However, every example talks about using a bode command. I try to put in the example from the book exactly how they have it just to test that it works. Everytime I use bode, Matlab states that it is an undefined variable or function. Im thinking my Matlab may be jacked up because none of the examples have anything about putting something to define bode which makes me think it should be built in. Can anyone verify if bode is a built in command in Matlab?