select - select rows from an ascii tab table.
SYNOPSYS
select 'selection expression' < tablefile
DESCRIPTION
select reads an ascii tab table from its standard input and prints the rows
for which the selection expression evaluates to true on the standard output.
The expression should be a valid awk language expression and may contain
references to column names and header keyword values.
OPTIONS
- -D
- Print out the awk program to be executed before forking.
- -H
- Specify an alternate file for the ascii tab table header. When the -H
option is given the input file should not have a header.
DETAILS
row and select are the same program. They are impliemnted by wrapping the
users selection expression into an awk labguage program and calling the awk
interpreter. The text of the program is simple the selection expression
itself. This works because awk's default action is to print the row to the
standard output.
ENVIRONMENT
- TABLEAWK
- the name of the awk interpreter to execute. The default
interpreter is tawk.
- TABLEFUNCTIONS
- a path specifying directories to find the source for
undefined functions.
SEE ALSO
- <starbase.1>
- ascii tab tables introduction.
- <starbase.5>
- ascii tab table file format.
- <#mawk>
- an implimentation of the awk programming language by Mike Brennan.
- <#tawk>
- awk language extensions implimented at SAO.
- <#slalink>
- a tawk extension for inclusion of the slalib astrometry
libraries.