RSEIS (version 2.1-6)

INVRft: Inverse Fourier Transform

Description

Inverse Fourier Transform

Usage

INVRft(G, n, tstart, dt)

Arguments

G

Input fourier transform

n

length of time vector

tstart

time series starts at tstart

dt

Delta t, sample rate

Value

• g
  truncate time vector to N points
• f
  frequencies
• t
  times

Details

G is a vector spectrum evaluated at positive and negative frequencies as defined by makefreq. tstart, dt and n define the output time vector as described above. g is the Inverse Fourier Transform of G scaled by dt. time shift theorem has been used to account for time not starting at t=0.

See Also

makefreq, FRWDft, INSTresponse

Examples

zil = rnorm(300)
fss = FRWDft( zil, length(zil), 0, 0.004)   
INVRft(fss$G, length(zil), 0, 0.004)