( This ( ( can ( be ( useful ( for ( estimating ( ( frequency ( -LRB- ( period -RRB- ) ) ) ( of ( individual waves ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (MD can) (VP (VB be) (ADJP (JJ useful) (PP (IN for) (S (VP (VBG estimating) (NP (NP (NP (NN frequency)) (PRN (-LRB- -LRB-) (NP (NN period)) (-RRB- -RRB-))) (PP (IN of) (NP (JJ individual) (NNS waves)))))))))) (. .)))
This can be useful for estimating frequency (period) of individual waves.
(ROOT (S (NP (NP (DT The) (NN frequency)) (PP (IN of) (NP (DT a) (NN wave)))) (VP (VBZ is) (NP (NP (DT the) (NN reciprocal)) (PP (IN of) (NP (NP (DT the) (NN period)) (PP (IN of) (NP (DT the) (NN wave))))))) (. .)))