SYNOPSIS
PERL PROGRAM NAME:
AUTHOR: Juan Lorenzo (Perl module only)
DATE:
DESCRIPTION:
Version:
USE
NOTES
Examples
SYNOPSIS
SEISMIC UNIX NOTES SURESAMP - Resample in time
suresamp <stdin >stdout [optional parameters]
Required parameters:
none
Optional Parameters:
nt=tr.ns number of time samples on output
dt= time sampling interval on output
default is:
tr.dt/10^6 seismic data
tr.d1 non-seismic data
tmin= time of first sample in output
default is:
tr.delrt/10^3 seismic data
tr.f1 non-seismic data
rf= resampling factor;
if defined, set nt=nt_in*rf and dt=dt_in/rf
verbose=0 =1 for advisory messages
Example 1: (assume original data had dt=.004 nt=256)
sufilter <data f=40,50 amps=1.,0. |
suresamp nt=128 dt=.008 | ...
Using the resampling factor rf, this example translates to:
sufilter <data f=40,50 amps=1.,0. | suresamp rf=0.5 | ...
Note the typical anti-alias filtering before sub-sampling!
Example 2: (assume original data had dt=.004 nt=256)
suresamp <data nt=512 dt=.002 | ...
or use:
suresamp <data rf=2 | ...
Example 3: (assume original data had d1=.1524 nt=8192)
sufilter <data f=0,1,3,3.28 amps=1,1,1,0 |
suresamp <data nt=4096 dt=.3048 | ...
Example 4: (assume original data had d1=.5 nt=4096)
suresamp <data nt=8192 dt=.25 | ...
Credits:
CWP: Dave (resamp algorithm), Jack (SU adaptation)
CENPET: Werner M. Heigl - modified for well log support
RISSC: Nils Maercklin 2006 - minor fixes, added rf option
Algorithm:
Resampling is done via 8-coefficient sinc-interpolation.
See "$CWPROOT/src/cwp/lib/intsinc8.c" for technical details.
Trace header fields accessed: ns, dt, delrt, d1, f1, trid
Trace header fields modified: ns, dt, delrt (only when set tmin)
d1, f1 (only when set tmin)User's notes (Juan Lorenzo) untested
CHANGES and their DATES
Import packages
instantiation of packages
Encapsulated hash of private variables
sub Step
collects switches and assembles bash instructions by adding the program name
sub note
collects switches and assembles bash instructions by adding the program name
sub clear
sub d1
sub dt
sub f
sub nt
sub rf
sub tmin
sub verbose
sub get_max_index
max index = number of input variables -1