Nyquist frequency signal, whereas "Nyquist frequency" is a property of a discrete-time system. When the function domain is time, sample rates are usually expressed in samples per second, and the unit of Nyquist frequency is cycles per second (hertz). When the function domain is distance, as in an image sampling system, the sample rate might be dots per inch and the corresponding Nyquist frequency would be in cycles/inch. Referring again to Figure 1, undersampling of the sinusoid at 0.6 f is what allows there to be a lower-frequency "alias", which is a different function that produces the same set of samples. That
Oh Dear! What Can the Matter Be? me a twopenny whistle He'll buy me a threepenny fair He'll buy me a Bunch o' Blue Ribbons To tye up my bonny Brown Hair O saw ye him coming And saw ye him coming O saw ye him coming Hame frae the Newcastle fair </poem> The following are given as the traditional lyrics (being chorus and verse) in Cuddon's and Preston's "A Dictionary of Literary Terms and Literary Theory": <poem> O dear, what can the matter be? Dear, dear, what can the matter be? O dear, what can the matter be? Johnny's so long at the fair. He promised