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casa::ScalarColumn< T > Class Template Reference

Access to a scalar table column with arbitrary data type. More...

#include <ScalarColumn.h>

Inheritance diagram for casa::ScalarColumn< T >:
casa::TableColumn

List of all members.

Public Member Functions

 ScalarColumn ()
 The default constructor creates a null object, i.e.
 ScalarColumn (const Table &, const String &columnName)
 Construct for the given column in the given table.
 ScalarColumn (const TableColumn &)
 Construct from the given table column.
 ScalarColumn (const ScalarColumn< T > &)
 Copy constructor (reference semantics).
 ~ScalarColumn ()
virtual TableColumnclone () const
 Clone the object.
ScalarColumn< T > & operator= (const ScalarColumn< T > &)
 Assignment uses reference semantics, thus works the same as function reference.
void reference (const ScalarColumn< T > &)
 Change the reference to another column.
void attach (const Table &table, const String &columnName)
 Attach a column to the object.
void get (uInt rownr, T &value) const
 Get the data from a particular cell (i.e.
get (uInt rownr) const
operator() (uInt rownr) const
void getColumn (Vector< T > &vec, Bool resize=False) const
 Get the vector of all values in the column.
Vector< T > getColumn () const
 Get the vector of all values in the column.
void getColumnRange (const Slicer &rowRange, Vector< T > &vec, Bool resize=False) const
 Get the vector of a range of values in the column.
Vector< T > getColumnRange (const Slicer &rowRange) const
 Get the vector of a range of values in the column.
void getColumnCells (const RefRows &rownrs, Vector< T > &vec, Bool resize=False) const
 Get the vector of some values in the column.
Vector< T > getColumnCells (const RefRows &rownrs) const
 Get the vector of some values in the column.
void put (uInt rownr, const T &value)
 Put the value in a particular cell (i.e.
void put (uInt rownr, const ScalarColumn< T > &that)
 Copy the value of a cell of that column to a cell of this column.
void put (uInt thisRownr, const ScalarColumn< T > &that, uInt thatRownr)
 Use possibly different row numbers for that (i.e.
void put (uInt rownr, const TableColumn &that)
 Copy the value of a cell of that column to a cell of this column.
void put (uInt thisRownr, const TableColumn &that, uInt thatRownr)
 Use possibly different row numbers for that (i.e.
void putColumn (const Vector< T > &vec)
 Put the vector of all values in the column.
void putColumnRange (const Slicer &rowRange, const Vector< T > &vec)
 Put the vector of a range of values in the column.
void putColumnCells (const RefRows &rownrs, const Vector< T > &vec)
 Put the vector of some values in the column.
void fillColumn (const T &value)
 Put the same value in all cells of the column.
void putColumn (const ScalarColumn< T > &that)
 Put the contents of a column with the same data type into this column.

Protected Attributes

Bool canAccessColumn_p
 Keep a switch to determine if an entire column can be accessed.
Bool reaskAccessColumn_p
 Keep a switch to know if access knowledge is permanent or has to be asked again the next time.

Private Member Functions

void checkDataType () const
 Check if the data type matches the column data type.

Detailed Description

template<class T>
class casa::ScalarColumn< T >

Access to a scalar table column with arbitrary data type.

Intended use:

Public interface

Review Status

Reviewed By:
dschieb
Date Reviewed:
1994/08/10
Test programs:
none

Prerequisite

Etymology

ScalarColumn<T> gives read and write access to a column in a table containing a scalar with data type T.

Synopsis

The class ScalarColumn allows read and write access to a column containing scalar values with an arbitrary data type. It is possible to get the data in an individual cell (i.e. table row) and to get the column as a whole.

A default constructor is defined to allow construction of an array of ScalarColumn objects. However, this constructs an object not referencing a column. Functions like get, etc. will fail (i.e. result in a segmentation fault) when used on such objects. The functions isNull and throwIfNull can be used to test on this. The functions attach and reference can fill in the object.

Example

See module Tables .

Definition at line 84 of file ScalarColumn.h.


Constructor & Destructor Documentation

template<class T>
casa::ScalarColumn< T >::ScalarColumn ( )

The default constructor creates a null object, i.e.

it does not reference a table column. The sole purpose of this constructor is to allow construction of an array of ScalarColumn objects. The functions reference and attach can be used to make a null object reference a column. Note that get functions, etc. will cause a segmentation fault when operating on a null object. It was felt it was too expensive to test on null over and over again. The user should use the isNull or throwIfNull function in case of doubt.

template<class T>
casa::ScalarColumn< T >::ScalarColumn ( const Table ,
const String columnName 
)

Construct for the given column in the given table.

template<class T>
casa::ScalarColumn< T >::ScalarColumn ( const TableColumn ) [explicit]

Construct from the given table column.

This constructor is useful if first a table column was constructed, its type is determined and thereafter used to construct the correct column object.

template<class T>
casa::ScalarColumn< T >::ScalarColumn ( const ScalarColumn< T > &  )

Copy constructor (reference semantics).

template<class T>
casa::ScalarColumn< T >::~ScalarColumn ( )

Member Function Documentation

template<class T>
void casa::ScalarColumn< T >::attach ( const Table table,
const String columnName 
) [inline]

Attach a column to the object.

This is in fact only a shorthand for
reference (ScalarColumn<T> (table, columnName));

Reimplemented from casa::TableColumn.

Definition at line 131 of file ScalarColumn.h.

template<class T>
void casa::ScalarColumn< T >::checkDataType ( ) const [private]

Check if the data type matches the column data type.

template<class T>
virtual TableColumn* casa::ScalarColumn< T >::clone ( ) const [virtual]

Clone the object.

Reimplemented from casa::TableColumn.

template<class T>
void casa::ScalarColumn< T >::fillColumn ( const T &  value)

Put the same value in all cells of the column.

template<class T>
void casa::ScalarColumn< T >::get ( uInt  rownr,
T &  value 
) const [inline]

Get the data from a particular cell (i.e.

table row). The row numbers count from 0 until #rows-1.

Definition at line 137 of file ScalarColumn.h.

template<class T>
T casa::ScalarColumn< T >::get ( uInt  rownr) const [inline]

Definition at line 147 of file ScalarColumn.h.

template<class T>
void casa::ScalarColumn< T >::getColumn ( Vector< T > &  vec,
Bool  resize = False 
) const

Get the vector of all values in the column.

According to the assignment rules of class Array, the destination vector must be empty or its length must be the number of cells in the column (i.e. the number of rows in the table).

template<class T>
Vector<T> casa::ScalarColumn< T >::getColumn ( ) const

Get the vector of all values in the column.

template<class T>
void casa::ScalarColumn< T >::getColumnCells ( const RefRows rownrs,
Vector< T > &  vec,
Bool  resize = False 
) const

Get the vector of some values in the column.

The Slicer object can be used to specify start, end (or length), and stride of the rows to get. According to the assignment rules of class Array, the destination vector must be empty or its length must be the number of cells in the column (i.e. the number of rows in the RefRows object).

template<class T>
Vector<T> casa::ScalarColumn< T >::getColumnCells ( const RefRows rownrs) const

Get the vector of some values in the column.

template<class T>
void casa::ScalarColumn< T >::getColumnRange ( const Slicer rowRange,
Vector< T > &  vec,
Bool  resize = False 
) const

Get the vector of a range of values in the column.

The Slicer object can be used to specify start, end (or length), and stride of the rows to get. According to the assignment rules of class Array, the destination vector must be empty or its length must be the number of cells in the column (i.e. the number of rows in the slicer).

template<class T>
Vector<T> casa::ScalarColumn< T >::getColumnRange ( const Slicer rowRange) const

Get the vector of a range of values in the column.

The Slicer object can be used to specify start, end (or length), and stride of the rows to get..

template<class T>
T casa::ScalarColumn< T >::operator() ( uInt  rownr) const [inline]

Definition at line 153 of file ScalarColumn.h.

template<class T>
ScalarColumn<T>& casa::ScalarColumn< T >::operator= ( const ScalarColumn< T > &  )

Assignment uses reference semantics, thus works the same as function reference.

template<class T>
void casa::ScalarColumn< T >::put ( uInt  rownr,
const T &  value 
) [inline]

Put the value in a particular cell (i.e.

table row). The row numbers count from 0 until #rows-1.

Definition at line 198 of file ScalarColumn.h.

template<class T>
void casa::ScalarColumn< T >::put ( uInt  rownr,
const ScalarColumn< T > &  that 
) [inline]

Copy the value of a cell of that column to a cell of this column.

The data types of both columns must be the same.

Use the same row numbers for both cells.

Definition at line 206 of file ScalarColumn.h.

Referenced by casa::ScalarColumn< Complex >::put().

template<class T>
void casa::ScalarColumn< T >::put ( uInt  thisRownr,
const ScalarColumn< T > &  that,
uInt  thatRownr 
)

Use possibly different row numbers for that (i.e.

input) and and this (i.e. output) cell.

template<class T>
void casa::ScalarColumn< T >::put ( uInt  rownr,
const TableColumn that 
) [inline]

Copy the value of a cell of that column to a cell of this column.

This function uses a generic TableColumn object as input. If possible the data will be promoted to the data type of this column. Otherwise an exception is thrown.

Use the same row numbers for both cells.

Reimplemented from casa::TableColumn.

Definition at line 219 of file ScalarColumn.h.

Referenced by casa::ScalarColumn< Complex >::put().

template<class T>
void casa::ScalarColumn< T >::put ( uInt  thisRownr,
const TableColumn that,
uInt  thatRownr 
) [virtual]

Use possibly different row numbers for that (i.e.

input) and and this (i.e. output) cell.

Reimplemented from casa::TableColumn.

template<class T>
void casa::ScalarColumn< T >::putColumn ( const Vector< T > &  vec)

Put the vector of all values in the column.

The length of the vector must be the number of cells in the column (i.e. the number of rows in the table).

template<class T>
void casa::ScalarColumn< T >::putColumn ( const ScalarColumn< T > &  that)

Put the contents of a column with the same data type into this column.

To put the contents of a column with a different data type into this column, the function TableColumn::putColumn can be used (provided the data type promotion is possible). In fact, this function is an assignment operator with copy semantics.

template<class T>
void casa::ScalarColumn< T >::putColumnCells ( const RefRows rownrs,
const Vector< T > &  vec 
)

Put the vector of some values in the column.

The length of the vector must be the number of cells in the RefRows object.

template<class T>
void casa::ScalarColumn< T >::putColumnRange ( const Slicer rowRange,
const Vector< T > &  vec 
)

Put the vector of a range of values in the column.

The Slicer object can be used to specify start, end (or length), and stride of the rows to put. The length of the vector must be the number of cells in the slice.

template<class T>
void casa::ScalarColumn< T >::reference ( const ScalarColumn< T > &  )

Change the reference to another column.

This is in fact an assignment operator with reference semantics. It removes the reference to the current column and creates a reference to the column referenced in the other object. It will handle null objects correctly.

Referenced by casa::ScalarColumn< Complex >::attach().


Member Data Documentation

template<class T>
Bool casa::ScalarColumn< T >::canAccessColumn_p [mutable, protected]

Keep a switch to determine if an entire column can be accessed.

True = yes; False = no.

Definition at line 259 of file ScalarColumn.h.

template<class T>
Bool casa::ScalarColumn< T >::reaskAccessColumn_p [mutable, protected]

Keep a switch to know if access knowledge is permanent or has to be asked again the next time.

Definition at line 262 of file ScalarColumn.h.


The documentation for this class was generated from the following file: