## IRAF Help page for: GAPFILL

GAPFILL (Jan93) grasp.grtools GAPFILL (Jan93)
NAME
gapfill -- Fill gaps in GONG time series via autoregressive
interpolation.
USAGE
gapfill input output maxlen fill_factor
PARAMETERS
input
Input time series image list.
output
Output gap-filled time series image list.
maxlen
Maximum Auto-regressive filter length.
fill_factor
Filling factor.
DESCRIPTION
GAPFILL uses a simplified autoregressive technique to fill short
gaps in the GONG time series. The positions of good data segments
are determined from the window funtion contained in the last row of
the input time series images.
The maximum AR filter length to be used is given by maxlen. Gaps
will not be filled unless their length is less than fill_factor
times the smaller of maxlen and the number of points in the largest
good segment adjacent to the gap.
The subroutine used was written by Tim Brown (HAO) and is described
in the paper "A Technique for Estimating Complicated Power Spectra
From Time Series with Gaps", Ap.J., 349, 667, 1990.
EXAMPLES
1. To gap fill a GONG time series:
gr> gapfill tcvdt921124d250 gftcvdt921124d250
TIME REQUIREMENTS
BUGS
SEE ALSO

Data Product Code Guide | Back to GRASP Help Page