DOCUMENTATION

SYNOPSIS

PERL PROGRAM NAME:  LAS2SU - convert las2 format well log curves to su traces	
AUTHOR: Juan Lorenzo (Perl module only)
DATE:   
DESCRIPTION:
Version: 

USE

NOTES

Examples

SEISMIC UNIX NOTES

 LAS2SU - convert las2 format well log curves to su traces	

  las2su <stdin nskip= ncurve= >stdout [optional params]	

 Required parameters:						
 none								
 Optional parameters:						
 ncurve=automatic	number of log curves in the las file	
 dz=0.5		input depth sampling (ft)		
 m=0			output (d1,f1) in feet			
			=1 output (d1,f1) in meters		
 ss=0			do not subsample (unless nz > 32767 )	
			=1 pass every other sample		
 verbose=0		=1 to echo las header lines to screen	
 outhdr=las_header.asc	name of file for las headers		

 Notes:							
 1. It is recommended to run LAS_CERTIFY available from CWLS	
    at http://cwls.org.					
 2. First log curve MUST BE depth.				
 3. If number of depth levels > 32767 (segy NT limit)		
    then input is subsampled by factor of 2 or 4 as needed	
 4. Logs may be isolated using tracl header word (1,2,...,ncurve) 
    tracl=1 is depth						

 If the input LAS file contains sonic data as delta t or interval
 transit time and you plan to use these data for generating a 
 reflection coefficient time series in suwellrf, convert the sonic
 trace to velocity using suop with op=s2v (sonic to velocity) 
 before input of the velocity trace to suwellrf.		", 

 Caveat:							", 
 No trap is made for the commonly used null value in LAS files 
 (-999.25). The null value will be output as ?999.25, which	
 really messes up a suxwigb display of density data because the
 ?999.25 skews the more or less 2.5 values of density.		
 The user needs to edit out null values (-999.25) before running
 other programs, such as "suwellrf".				


 Credits:
  *	Chris Liner based on code by Ferhan Ahmed and a2b.c (June 2005)
  *            (Based on code by Ferhan Ahmed and a2b.c)
  *            I gratefully acknowledge Saudi Aramco for permission
  *            to release this code developed while I worked for the
  *            EXPEC-ARC research division.
  *	CWP: John Stockwell 31 Oct 2006, combining lasstrip and
  *	CENPET: lasstrip 2006 by Werner Heigl
  *
  *     Rob Hardy: allow the ncurve parameter to work correctly if set
  *    - change string length to 400 characters to allow more curves
  *    - note nskip in header is totally ignored !
  *
  * Ideas for improvement:
  *	add option to chop off part of logs (often shallow
  *	   portions are not of interest
  *	cross check sampling interval from header against
  *	   values found from first log curve (=depth)
  *
 

CHANGES and their DATES

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 dz

sub m

sub ncurve

sub nskip

sub outhdr

sub ss

sub verbose

sub get_max_index

max index = number of input variables -1