Package uk.ac.starlink.ttools.filter
Class KeepColumnFilter
- java.lang.Object
-
- uk.ac.starlink.ttools.filter.BasicFilter
-
- uk.ac.starlink.ttools.filter.KeepColumnFilter
-
- All Implemented Interfaces:
ProcessingFilter
public class KeepColumnFilter extends BasicFilter
Table filter for selecting a number of columns and discarding the rest.- Since:
- 3 Mar 2005
- Author:
- Mark Taylor (Starlink)
-
-
Constructor Summary
Constructors Constructor Description KeepColumnFilter()
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description ProcessingStep
createStep(java.util.Iterator argIt)
Creates a new ProcessingStep based on a sequence of command-line arguments.protected java.lang.String[]
getDescriptionLines()
static uk.ac.starlink.table.StarTable
keepColumnTable(uk.ac.starlink.table.StarTable table, java.lang.String colIdList)
Returns a table which selects a number of columns from its base table by column ID.-
Methods inherited from class uk.ac.starlink.ttools.filter.BasicFilter
explainSyntax, getDescription, getName, getUsage
-
-
-
-
Method Detail
-
getDescriptionLines
protected java.lang.String[] getDescriptionLines()
- Specified by:
getDescriptionLines
in classBasicFilter
-
createStep
public ProcessingStep createStep(java.util.Iterator argIt) throws ArgException
Description copied from interface:ProcessingFilter
Creates a new ProcessingStep based on a sequence of command-line arguments. The argIt argument is an iterator over the command-line arguments positioned just before any arguments intended for this filter. If legal, any that can be comprehended by this filter should be read (iterated over) and removed, and a ProcessingStep should accordingly be returned. In the case of a successful return, it is essential that no arguments other than the ones intended for this filter are read from the iterator.If the argument list is badly-formed as far as this filter is concerned, an
ArgException
should be thrown. If itsusageFrament
is blank, it will be filled in later using this mode's usage text.- Parameters:
argIt
- iterator over command-line arguments positioned at the first one- Throws:
ArgException
-
keepColumnTable
public static uk.ac.starlink.table.StarTable keepColumnTable(uk.ac.starlink.table.StarTable table, java.lang.String colIdList) throws java.io.IOException
Returns a table which selects a number of columns from its base table by column ID.- Parameters:
table
- base tablecolIdList
- list of column IDs, one for each column in the output table- Returns:
- new table using columns selected from table
- Throws:
java.io.IOException
-
-