#include <CompressFloat.h>

Public Member Functions
	CompressFloat (const String &virtualColumnName, const String &storedColumnName, Float scale, Float offset=0)
	Construct an engine to scale all arrays in a column with the given offset and scale factor. More...

	CompressFloat (const String &virtualColumnName, const String &storedColumnName, const String &scaleColumnName, const String &offsetColumnName, Bool autoScale=True)
	Construct an engine to scale the arrays in a column. More...

	CompressFloat (const Record &spec)
	Construct from a record specification as created by getmanagerSpec(). More...

	~CompressFloat ()
	Destructor is mandatory. More...

virtual String	dataManagerType () const
	Return the type name of the engine (i.e. More...

virtual String	dataManagerName () const
	Get the name given to the engine (is the virtual column name). More...

virtual Record	dataManagerSpec () const
	Record a record containing data manager specifications. More...

Public Member Functions inherited from casacore::BaseMappedArrayEngine< Float, Short >
const String &	virtualName () const
	Get the virtual column name. More...

const String &	storedName () const
	Get the stored column name. More...

virtual Bool	isWritable () const
	The column is writable if the underlying stored column is writable. More...

Public Member Functions inherited from casacore::VirtualColumnEngine
	VirtualColumnEngine ()
	Create the object. More...

virtual	~VirtualColumnEngine ()

Public Member Functions inherited from casacore::DataManager
	DataManager ()
	Default constructor. More...

virtual	~DataManager ()

void	dataManagerInfo (Record &info) const
	Add SEQNR and SPEC (the DataManagerSpec subrecord) to the info. More...

virtual Record	getProperties () const
	Get data manager properties that can be modified. More...

virtual void	setProperties (const Record &spec)
	Modify data manager properties given in record fields. More...

virtual Bool	canReallocateColumns () const
	Tell if the data manager wants to reallocate the data manager column objects. More...

virtual DataManagerColumn *	reallocateColumn (DataManagerColumn *column)
	Reallocate the column object if it is part of this data manager. More...

uInt	sequenceNr () const
	Get the (unique) sequence nr of this data manager. More...

uInt	ncolumn () const
	Get the nr of columns in this data manager (can be zero). More...

Bool	asBigEndian () const
	Have the data to be stored in big or little endian canonical format? More...

const TSMOption &	tsmOption () const
	Get the TSM option. More...

MultiFileBase *	multiFile ()
	Get the MultiFile pointer (can be 0). More...

String	keywordName (const String &keyword) const
	Compose a keyword name from the given keyword appended with the sequence number (e.g. More...

String	fileName () const
	Compose a unique filename from the table name and sequence number. More...

ByteIO::OpenOption	fileOption () const
	Get the AipsIO option of the underlying file. More...

virtual Bool	isRegular () const
	Is this a regular storage manager? It is regular if it allows addition of rows and writing data in them. More...

Table &	table () const
	Get the table this object is associated with. More...

virtual Bool	canAddColumn () const
	Does the data manager allow to add columns? (default no) More...

virtual Bool	canRemoveColumn () const
	Does the data manager allow to delete columns? (default no) More...

virtual Bool	canRenameColumn () const
	Does the data manager allow to rename columns? (default yes) More...

virtual void	setMaximumCacheSize (uInt nMiB)
	Set the maximum cache size (in bytes) to be used by a storage manager. More...

virtual void	showCacheStatistics (std::ostream &) const
	Show the data manager's IO statistics. More...

DataManagerColumn *	createScalarColumn (const String &columnName, int dataType, const String &dataTypeId)
	Create a column in the data manager on behalf of a table column. More...

DataManagerColumn *	createDirArrColumn (const String &columnName, int dataType, const String &dataTypeId)
	Create a direct array column. More...

DataManagerColumn *	createIndArrColumn (const String &columnName, int dataType, const String &dataTypeId)
	Create an indirect array column. More...

DataManager *	getClone () const
	Has the object already been cloned? More...

void	setClone (DataManager *clone) const
	Set the pointer to the clone. More...

Public Member Functions inherited from casacore::VirtualArrayColumn< T >
	VirtualArrayColumn ()
	Create a column. More...

virtual	~VirtualArrayColumn ()

virtual int	dataType () const
	Return the data type of the column. More...

virtual String	dataTypeId () const
	Return the data type Id of the column. More...

Public Member Functions inherited from casacore::VirtualArrayColumnBase
	VirtualArrayColumnBase ()
	Create a column. More...

virtual	~VirtualArrayColumnBase ()

Public Member Functions inherited from casacore::DataManagerColumn
	DataManagerColumn ()
	Create a column. More...

virtual	~DataManagerColumn ()
	Frees up the storage. More...

void	setIsFixedShape (Bool isFixedShape)
	Set the isFixedShape flag. More...

Bool	isFixedShape () const
	Is this a fixed shape column? More...

virtual void	setMaxLength (uInt maxLength)
	Set the maximum length of the value (can be used for strings). More...

void	setFixedShapeColumn (const IPosition &shape)
	Set the shape of all (fixed-shaped) arrays in the column. More...

virtual void	setShapeTiled (rownr_t rownr, const IPosition &shape, const IPosition &tileShape)
	Set the shape and tile shape of an (variable-shaped) array in the given row. More...

virtual IPosition	tileShape (rownr_t rownr)
	Get the tile shape of the item in the given row. More...

ColumnCache &	columnCache ()
	Get access to the ColumnCache object. More...

const ColumnCache *	columnCachePtr () const

void	get (rownr_t rownr, Bool *dataPtr)
	Get the scalar value in the given row. More...

void	get (rownr_t rownr, uChar *dataPtr)

void	get (rownr_t rownr, Short *dataPtr)

void	get (rownr_t rownr, uShort *dataPtr)

void	get (rownr_t rownr, Int *dataPtr)

void	get (rownr_t rownr, uInt *dataPtr)

void	get (rownr_t rownr, Int64 *dataPtr)

void	get (rownr_t rownr, float *dataPtr)

void	get (rownr_t rownr, double *dataPtr)

void	get (rownr_t rownr, Complex *dataPtr)

void	get (rownr_t rownr, DComplex *dataPtr)

void	get (rownr_t rownr, String *dataPtr)

void	get (rownr_t rownr, void *dataPtr)
	This function is the get for all non-standard data types. More...

void	put (rownr_t rownr, const Bool *dataPtr)
	Put the scalar value into the given row. More...

void	put (rownr_t rownr, const uChar *dataPtr)

void	put (rownr_t rownr, const Short *dataPtr)

void	put (rownr_t rownr, const uShort *dataPtr)

void	put (rownr_t rownr, const Int *dataPtr)

void	put (rownr_t rownr, const uInt *dataPtr)

void	put (rownr_t rownr, const Int64 *dataPtr)

void	put (rownr_t rownr, const float *dataPtr)

void	put (rownr_t rownr, const double *dataPtr)

void	put (rownr_t rownr, const Complex *dataPtr)

void	put (rownr_t rownr, const DComplex *dataPtr)

void	put (rownr_t rownr, const String *dataPtr)

void	put (rownr_t rownr, const void *dataPtr)
	This function is the put for all non-standard data types. More...

void	throwGet () const
	Throw an "invalid operation" exception for the default implementation of get. More...

void	throwPut () const
	Throw an "invalid operation" exception for the default implementation of put. More...

void	setColumnName (const String &colName)
	Set the column name. More...

const String &	columnName () const
	Get rhe column name. More...

Static Public Member Functions
static String	className ()
	Return the name of the class. More...

static void	registerClass ()
	Register the class name and the static makeObject "constructor". More...

static DataManager *	makeObject (const String &dataManagerType, const Record &spec)
	Define the "constructor" to construct this engine when a table is read back. More...

Static Public Member Functions inherited from casacore::DataManager
static void	registerCtor (const String &type, DataManagerCtor func)
	Register a mapping of a data manager type to its static construction function. More...

static DataManagerCtor	getCtor (const String &dataManagerType)
	Get the "constructor" of a data manager (thread-safe). More...

static Bool	isRegistered (const String &dataManagerType)
	Test if a data manager is registered (thread-safe). More...

static DataManager *	unknownDataManager (const String &dataManagerType, const Record &spec)
	Serve as default function for theirRegisterMap, which catches all unknown data manager types. More...

Private Member Functions
	CompressFloat (const CompressFloat &)
	Copy constructor is only used by clone(). More...

CompressFloat &	operator= (const CompressFloat &)
	Assignment is not needed and therefore forbidden (so it is made private and not implemented). More...

virtual DataManager *	clone () const
	Clone the engine object. More...

virtual void	create64 (rownr_t initialNrrow)
	Initialize the object for a new table. More...

virtual void	prepare ()
	Preparing consists of setting the writable switch and adding the initial number of rows in case of create. More...

virtual void	reopenRW ()
	Reopen the engine for read/write access. More...

virtual void	addRowInit (rownr_t startRow, rownr_t nrrow)
	Add rows to the table. More...

virtual void	getArray (rownr_t rownr, Array< Float > &array)
	Get an array in the given row. More...

virtual void	putArray (rownr_t rownr, const Array< Float > &array)
	Put an array in the given row. More...

virtual void	getSlice (rownr_t rownr, const Slicer &slicer, Array< Float > &array)
	Get a section of the array in the given row. More...

virtual void	putSlice (rownr_t rownr, const Slicer &slicer, const Array< Float > &array)
	Put into a section of the array in the given row. More...

virtual void	getArrayColumn (Array< Float > &array)
	Get an entire column. More...

virtual void	putArrayColumn (const Array< Float > &array)
	Put an entire column. More...

virtual void	getArrayColumnCells (const RefRows &rownrs, Array< Float > &data)
	Get some array values in the column. More...

virtual void	putArrayColumnCells (const RefRows &rownrs, const Array< Float > &data)
	Put some array values in the column. More...

virtual void	getColumnSlice (const Slicer &slicer, Array< Float > &array)
	Get a section of all arrays in the column. More...

virtual void	putColumnSlice (const Slicer &slicer, const Array< Float > &array)
	Put a section of all arrays in the column. More...

virtual void	getColumnSliceCells (const RefRows &rownrs, const Slicer &slicer, Array< Float > &data)
	Get a section of some arrays in the column. More...

virtual void	putColumnSliceCells (const RefRows &rownrs, const Slicer &slicer, const Array< Float > &data)
	Put into a section of some arrays in the column. More...

void	scaleOnGet (Float scale, Float offset, Array< Float > &array, const Array< Short > &target)
	Scale and/or offset target to array. More...

void	scaleOnPut (Float scale, Float offset, const Array< Float > &array, Array< Short > &target)
	Scale and/or offset array to target. More...

void	scaleColumnOnGet (Array< Float > &array, const Array< Short > &target)
	Scale and/or offset target to array for the entire column. More...

void	scaleColumnOnPut (const Array< Float > &array, Array< Short > &target)
	Scale and/or offset array to target for the entire column. More...

Float	getScale (rownr_t rownr)
	Get the scale value for this row. More...

Float	getOffset (rownr_t rownr)
	Get the offset value for this row. More...

void	findMinMax (Float &minVal, Float &maxVal, const Array< Float > &array) const
	Find minimum and maximum from the array data. More...

void	makeScaleOffset (Float &scale, Float &offset, Float minVal, Float maxVal) const
	Make scale and offset from the minimum and maximum of the array data. More...

void	putPart (rownr_t rownr, const Slicer &slicer, const Array< Float > &array, Float scale, Float offset)
	Put a part of an array in a row using given scale/offset values. More...

void	putFullPart (rownr_t rownr, const Slicer &slicer, Array< Float > &fullArray, const Array< Float > &partArray, Float minVal, Float maxVal)
	Fill the array part into the full array and put it using the given min/max values. More...

Private Attributes
String	scaleName_p

String	offsetName_p

Float	scale_p

Float	offset_p

Bool	fixed_p

Bool	autoScale_p

ScalarColumn< Float > *	scaleColumn_p

ScalarColumn< Float > *	offsetColumn_p

Array< Short >	buffer_p

Additional Inherited Members
Static Public Attributes inherited from casacore::DataManager
static rownr_t	MAXROWNR32
	Define the highest row number that can be represented as signed 32-bit. More...

Protected Member Functions inherited from casacore::BaseMappedArrayEngine< Float, Short >
	BaseMappedArrayEngine (const String &virtualColumnName, const String &storedColumnName)
	Construct an engine to convert the virtual column to the stored column. More...

	BaseMappedArrayEngine ()
	The default constructor is required for reconstruction of the engine when a table is read back. More...

	BaseMappedArrayEngine (const BaseMappedArrayEngine< Float, Short > &)
	Copy constructor is only used by copy constructor of derived classes. More...

	~BaseMappedArrayEngine ()
	Destructor is mandatory. More...

void	setWritable (Bool isWritable)
	Set if the column is writable or not. More...

void	setNames (const String &virtualName, const String &storedName)
	Set the virtual and stored column name. More...

ArrayColumn< Short > &	column ()
	Give access to the stored column. More...

virtual DataManagerColumn *	makeIndArrColumn (const String &columnName, int dataType, const String &dataTypeId)
	Create the column object for the array column in this engine. More...

void	prepare1 ()
	Do the 2 stages of the prepare (define columns and adding rows). More...

void	prepare2 ()

virtual void	addRow64 (rownr_t nrrow)
	Rows are added to the end of the table. More...

virtual void	setShapeColumn (const IPosition &shape)
	Set the shape of the FixedShape arrays in the column. More...

virtual void	setShape (rownr_t rownr, const IPosition &shape)
	Define the shape of the array in the given row. More...

virtual Bool	isShapeDefined (rownr_t rownr)
	Test if the (underlying) array is defined in the given row. More...

virtual uInt	ndim (rownr_t rownr)
	Get the dimensionality of the (underlying) array in the given row. More...

virtual IPosition	shape (rownr_t rownr)
	Get the shape of the (underlying) array in the given row. More...

virtual Bool	canChangeShape () const
	The data manager can handle changing the shape of an existing array when the underlying stored column can do it. More...

TableColumn	makeTableColumn (const String &columnName)
	Make a table column object for the given column. More...

void	getColumnSlice (const Slicer &slicer, Array< Float > &array)
	Get a section of all arrays in the column. More...

void	putColumnSlice (const Slicer &slicer, const Array< Float > &array)
	Put a section of all arrays in the column. More...

virtual IPosition	getStoredShape (rownr_t rownr, const IPosition &virtualShape)
	Map the virtual shape to the stored shape. More...

virtual Slicer	getStoredSlicer (const Slicer &virtualSlicer) const
	Map the slicer for a virtual shape to a stored shape. More...

virtual void	mapOnGet (Array< Float > &array, const Array< Short > &stored)
	Map StoredType array to VirtualType array. More...

virtual void	mapOnPut (const Array< Float > &array, Array< Short > &stored)
	Map Bool array to bit flags array. More...

Protected Member Functions inherited from casacore::DataManager
void	decrementNcolumn ()
	Decrement number of columns (in case a column is deleted). More...

void	setEndian (Bool bigEndian)
	Tell the data manager if big or little endian format is needed. More...

void	setTsmOption (const TSMOption &tsmOption)
	Tell the data manager which TSM option to use. More...

void	setMultiFile (MultiFileBase *mfile)
	Tell the data manager that MultiFile can be used. More...

virtual Bool	hasMultiFileSupport () const
	Does the data manager support use of MultiFile? A derived class has to return True if it can use the MultiFile. More...

void	throwDataTypeOther (const String &columnName, int dataType) const
	Throw an exception in case data type is TpOther, because the storage managers (and maybe other data managers) do not support such columns. More...

Protected Member Functions inherited from casacore::VirtualArrayColumn< T >
virtual void	getArray (rownr_t rownr, Array< T > &data)=0
	Get the array value in the given row. More...

virtual void	putArray (rownr_t rownr, const Array< T > &data)
	Put the array value into the given row. More...

virtual void	getSlice (rownr_t rownr, const Slicer &slicer, Array< T > &data)
	Get a section of the array in the given row. More...

virtual void	putSlice (rownr_t rownr, const Slicer &slicer, const Array< T > &data)
	Put into a section of the array in the given row. More...

virtual void	getArrayColumn (Array< T > &data)
	Get an entire column. More...

virtual void	putArrayColumn (const Array< T > &data)
	Put an entire column. More...

virtual void	getArrayColumnCells (const RefRows &rownrs, Array< T > &data)
	Get some array values in the column. More...

virtual void	putArrayColumnCells (const RefRows &rownrs, const Array< T > &data)
	Put some array values in the column. More...

virtual void	getColumnSlice (const Slicer &slicer, Array< T > &data)
	Get a section of all arrays in the column. More...

virtual void	putColumnSlice (const Slicer &slicer, const Array< T > &data)
	Put a section of all arrays in the column. More...

virtual void	getColumnSliceCells (const RefRows &rownrs, const Slicer &slicer, Array< T > &data)
	Get a section of some arrays in the column. More...

virtual void	putColumnSliceCells (const RefRows &rownrs, const Slicer &slicer, const Array< T > &data)
	Put into a section of some arrays in the column. More...

Protected Member Functions inherited from casacore::VirtualArrayColumnBase
virtual void	getScalarColumnV (ArrayBase &dataPtr)
	The scalar access functions throw an exception. More...

virtual void	putScalarColumnV (const ArrayBase &dataPtr)
	Put all scalar values in the column. More...

virtual void	getScalarColumnCellsV (const RefRows &rownrs, ArrayBase &dataPtr)
	Get some scalar values in the column. More...

virtual void	putScalarColumnCellsV (const RefRows &rownrs, const ArrayBase &dataPtr)
	Put some scalar values in the column. More...

Protected Member Functions inherited from casacore::DataManagerColumn
virtual void	getBool (rownr_t rownr, Bool *dataPtr)
	Get the scalar value in the given row. More...

virtual void	getuChar (rownr_t rownr, uChar *dataPtr)

virtual void	getShort (rownr_t rownr, Short *dataPtr)

virtual void	getuShort (rownr_t rownr, uShort *dataPtr)

virtual void	getInt (rownr_t rownr, Int *dataPtr)

virtual void	getuInt (rownr_t rownr, uInt *dataPtr)

virtual void	getInt64 (rownr_t rownr, Int64 *dataPtr)

virtual void	getfloat (rownr_t rownr, float *dataPtr)

virtual void	getdouble (rownr_t rownr, double *dataPtr)

virtual void	getComplex (rownr_t rownr, Complex *dataPtr)

virtual void	getDComplex (rownr_t rownr, DComplex *dataPtr)

virtual void	getString (rownr_t rownr, String *dataPtr)

virtual void	getOther (rownr_t rownr, void *dataPtr)
	This function is the get for all non-standard data types. More...

virtual void	putBool (rownr_t rownr, const Bool *dataPtr)
	Put the scalar value into the given row. More...

virtual void	putuChar (rownr_t rownr, const uChar *dataPtr)

virtual void	putShort (rownr_t rownr, const Short *dataPtr)

virtual void	putuShort (rownr_t rownr, const uShort *dataPtr)

virtual void	putInt (rownr_t rownr, const Int *dataPtr)

virtual void	putuInt (rownr_t rownr, const uInt *dataPtr)

virtual void	putInt64 (rownr_t rownr, const Int64 *dataPtr)

virtual void	putfloat (rownr_t rownr, const float *dataPtr)

virtual void	putdouble (rownr_t rownr, const double *dataPtr)

virtual void	putComplex (rownr_t rownr, const Complex *dataPtr)

virtual void	putDComplex (rownr_t rownr, const DComplex *dataPtr)

virtual void	putString (rownr_t rownr, const String *dataPtr)

virtual void	putOther (rownr_t rownr, const void *dataPtr)
	This function is the put for all non-standard data types. More...

void	getScalarColumnBase (ArrayBase &dataPtr)
	The default implementations of get and put functions. More...

void	putScalarColumnBase (const ArrayBase &dataPtr)

void	getScalarColumnCellsBase (const RefRows &rownrs, ArrayBase &dataPtr)

void	putScalarColumnCellsBase (const RefRows &rownrs, const ArrayBase &dataPtr)

void	getArrayColumnBase (ArrayBase &data)

void	putArrayColumnBase (const ArrayBase &data)

void	getArrayColumnCellsBase (const RefRows &rownrs, ArrayBase &data)

void	putArrayColumnCellsBase (const RefRows &rownrs, const ArrayBase &data)

void	getSliceBase (rownr_t rownr, const Slicer &slicer, ArrayBase &data)

void	putSliceBase (rownr_t rownr, const Slicer &slicer, const ArrayBase &data)

void	getColumnSliceBase (const Slicer &slicer, ArrayBase &data)

void	putColumnSliceBase (const Slicer &slicer, const ArrayBase &data)

void	getColumnSliceCellsBase (const RefRows &rownrs, const Slicer &slicer, ArrayBase &data)

void	putColumnSliceCellsBase (const RefRows &rownrs, const Slicer &slicer, const ArrayBase &data)

Detailed Description

Virtual column engine to scale a table float array

Intended use:

Public interface

Review Status

Reviewed By:: UNKNOWN
Date Reviewed:: before2004/08/25
Test programs:: tCompressFloat

Prerequisite

Synopsis

CompressFloat is a virtual column engine which scales an array of one type to another type to save disk storage. This resembles the classic AIPS compress method which scales the data from float to short. The scale factor and offset values can be given in two ways:

As a fixed values which is used for all arrays in the column. These values have to be given when constructing of the engine.
As the name of a column. In this way each array in the column has its own scale and offset value. By default it uses auto-scaling (see below). Otherwise the scale and offset value in a row must be put before the array is put and should not be changed anymore.

Auto-scaling means that the engine will determine the scale and offset value itself when an array (or a slice) is put. It does it by mapping the values in the array to the range [-32767,32767]. At each put the scale/offset values are changed as needed. Note that with auto-scaling putSlice can be somewhat slower, because the entire array might need to be rescaled.

As in FITS the scale and offset values are used as:
True_value = Stored_value * scale + offset;

An engine object should be used for one column only, because the stored column name is part of the engine. If it would be used for more than one column, they would all share the same stored column. When the engine is bound to a column, it is checked if the name of that column matches the given virtual column name.

The engine can be used for a column containing any kind of array (thus direct or indirect, fixed or variable shaped)) as long as the virtual array can be stored in the stored array. Thus a fixed shaped virtual can use a variable shaped stored, but not vice versa. A fixed shape indirect virtual can use a stored with direct arrays.

This class can also serve as an example of how to implement a virtual column engine.

Motivation

This class allows to store data in a smaller representation. It is needed to resemble the classic AIPS compress option.

Because the engine can serve only one column, it was possible to combine the engine and the column functionality in one class.

Example

// Create the table description and 2 columns with indirect arrays in it.
// The Int column will be stored, while the double will be
// used as virtual.
TableDesc tableDesc ("", TableDesc::Scratch);
tableDesc.addColumn (ArrayColumnDesc<Short> ("storedArray"));
tableDesc.addColumn (ArrayColumnDesc<Float> ("virtualArray"));
tableDesc.addColumn (ScalarColumnDesc<Float> ("scale"));
tableDesc.addColumn (ScalarColumnDesc<Float> ("offset"));
 
// Create a new table using the table description.
SetupNewTable newtab (tableDesc, "tab.data", Table::New);
 
// Create the array scaling engine (with auto-scale)
// and bind it to the float column.
CompressFloat scalingEngine("virtualArray", "storedArray",
"scale", "offset");
newtab.bindColumn ("virtualArray", scalingEngine);
// Create the table.
Table table (newtab);
 
// Store a 3-D array (with dim. 2,3,4) into each row of the column.
// The shape of each array in the column is implicitly set by the put
// function. This will also set the shape of the underlying Int array.
ArrayColumn data (table, "virtualArray");
Array<double> someArray(IPosition(4,2,3,4));
someArray = 0;
for (rownr_t i=0, i<10; i++) {          // table will have 10 rows
table.addRow();
data.put (i, someArray)
}

Definition at line 139 of file CompressFloat.h.

Constructor & Destructor Documentation

◆ CompressFloat() [1/4]

casacore::CompressFloat::CompressFloat	(	const String &	virtualColumnName,
		const String &	storedColumnName,
		Float	scale,
		Float	offset = `0`
	)

Construct an engine to scale all arrays in a column with the given offset and scale factor.

StoredColumnName is the name of the column where the scaled data will be put and must have data type Short. The virtual column using this engine must have data type Float.

◆ CompressFloat() [2/4]

casacore::CompressFloat::CompressFloat	(	const String &	virtualColumnName,
		const String &	storedColumnName,
		const String &	scaleColumnName,
		const String &	offsetColumnName,
		Bool	autoScale = `True`
	)

Construct an engine to scale the arrays in a column.

The scale and offset values are taken from a column with the given names. In that way each array has its own scale factor and offset value. An exception is thrown if these columns do not exist. VirtualColumnName is the name of the virtual column and is used to check if the engine gets bound to the correct column. StoredColumnName is the name of the column where the scaled data will be put and must have data type Short. The virtual column using this engine must have data type Float.

◆ CompressFloat() [3/4]

casacore::CompressFloat::CompressFloat ( const Record & spec )

Construct from a record specification as created by getmanagerSpec().

◆ ~CompressFloat()

casacore::CompressFloat::~CompressFloat ( )

Destructor is mandatory.

◆ CompressFloat() [4/4]

casacore::CompressFloat::CompressFloat ( const CompressFloat & )

private

Copy constructor is only used by clone().

(so it is made private).

Member Function Documentation

◆ addRowInit()

virtual void casacore::CompressFloat::addRowInit	(	rownr_t	startRow,
		rownr_t	nrrow
	)

privatevirtual

Add rows to the table.

If auto-scaling, it initializes the scale column with 0 to indicate that no data has been processed yet.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ className()

static String casacore::CompressFloat::className ( )

static

Return the name of the class.

This includes the names of the template arguments.

◆ clone()

virtual DataManager* casacore::CompressFloat::clone ( ) const

privatevirtual

Clone the engine object.

Implements casacore::DataManager.

◆ create64()

virtual void casacore::CompressFloat::create64 ( rownr_t initialNrrow )

privatevirtual

Initialize the object for a new table.

It defines the keywords containing the engine parameters.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ dataManagerName()

virtual String casacore::CompressFloat::dataManagerName ( ) const

virtual

Get the name given to the engine (is the virtual column name).

Reimplemented from casacore::DataManager.

◆ dataManagerSpec()

virtual Record casacore::CompressFloat::dataManagerSpec ( ) const

virtual

Record a record containing data manager specifications.

Reimplemented from casacore::DataManager.

◆ dataManagerType()

virtual String casacore::CompressFloat::dataManagerType ( ) const

virtual

Return the type name of the engine (i.e.

its class name).

Implements casacore::DataManager.

◆ findMinMax()

void casacore::CompressFloat::findMinMax	(	Float &	minVal,
		Float &	maxVal,
		const Array< Float > &	array
	)		const

private

Find minimum and maximum from the array data.

NaN and infinite values are ignored. If no values are finite, minimum and maximum are set to NaN.

◆ getArray()

virtual void casacore::CompressFloat::getArray	(	rownr_t	rownr,
		Array< Float > &	array
	)

privatevirtual

Get an array in the given row.

This will scale and offset from the underlying array.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ getArrayColumn()

virtual void casacore::CompressFloat::getArrayColumn ( Array< Float > & array )

privatevirtual

Get an entire column.

This will scale and offset from the underlying array.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ getArrayColumnCells()

virtual void casacore::CompressFloat::getArrayColumnCells	(	const RefRows &	rownrs,
		Array< Float > &	data
	)

privatevirtual

Get some array values in the column.

This will scale and offset from the underlying array.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ getColumnSlice()

virtual void casacore::CompressFloat::getColumnSlice	(	const Slicer &	slicer,
		Array< Float > &	array
	)

privatevirtual

Get a section of all arrays in the column.

This will scale and offset from the underlying array.

◆ getColumnSliceCells()

virtual void casacore::CompressFloat::getColumnSliceCells	(	const RefRows &	rownrs,
		const Slicer &	slicer,
		Array< Float > &	data
	)

privatevirtual

Get a section of some arrays in the column.

This will scale and offset from the underlying array.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ getOffset()

Float casacore::CompressFloat::getOffset ( rownr_t rownr )

inlineprivate

Get the offset value for this row.

Definition at line 364 of file CompressFloat.h.

References fixed_p, offset_p, and offsetColumn_p.

◆ getScale()

Float casacore::CompressFloat::getScale ( rownr_t rownr )

inlineprivate

Get the scale value for this row.

Definition at line 360 of file CompressFloat.h.

References fixed_p, scale_p, and scaleColumn_p.

◆ getSlice()

virtual void casacore::CompressFloat::getSlice	(	rownr_t	rownr,
		const Slicer &	slicer,
		Array< Float > &	array
	)

privatevirtual

Get a section of the array in the given row.

This will scale and offset from the underlying array.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ makeObject()

static DataManager* casacore::CompressFloat::makeObject	(	const String &	dataManagerType,
		const Record &	spec
	)

static

Define the "constructor" to construct this engine when a table is read back.

This "constructor" has to be registered by the user of the engine. If the engine is commonly used, its registration can be added to the registerAllCtor function in DataManager.cc. That function gets automatically invoked by the table system.

◆ makeScaleOffset()

void casacore::CompressFloat::makeScaleOffset	(	Float &	scale,
		Float &	offset,
		Float	minVal,
		Float	maxVal
	)		const

private

Make scale and offset from the minimum and maximum of the array data.

If minVal is NaN, scale is set to 0.

◆ operator=()

CompressFloat& casacore::CompressFloat::operator= ( const CompressFloat & )

private

Assignment is not needed and therefore forbidden (so it is made private and not implemented).

◆ prepare()

virtual void casacore::CompressFloat::prepare ( )

privatevirtual

Preparing consists of setting the writable switch and adding the initial number of rows in case of create.

Furthermore it reads the keywords containing the engine parameters.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ putArray()

virtual void casacore::CompressFloat::putArray	(	rownr_t	rownr,
		const Array< Float > &	array
	)

privatevirtual

Put an array in the given row.

This will scale and offset to the underlying array.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ putArrayColumn()

virtual void casacore::CompressFloat::putArrayColumn ( const Array< Float > & array )

privatevirtual

Put an entire column.

This will scale and offset to the underlying array.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ putArrayColumnCells()

virtual void casacore::CompressFloat::putArrayColumnCells	(	const RefRows &	rownrs,
		const Array< Float > &	data
	)

privatevirtual

Put some array values in the column.

This will scale and offset to the underlying array.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ putColumnSlice()

virtual void casacore::CompressFloat::putColumnSlice	(	const Slicer &	slicer,
		const Array< Float > &	array
	)

privatevirtual

Put a section of all arrays in the column.

This will scale and offset to the underlying array.

◆ putColumnSliceCells()

virtual void casacore::CompressFloat::putColumnSliceCells	(	const RefRows &	rownrs,
		const Slicer &	slicer,
		const Array< Float > &	data
	)

privatevirtual

Put into a section of some arrays in the column.

This will scale and offset to the underlying array.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ putFullPart()

void casacore::CompressFloat::putFullPart	(	rownr_t	rownr,
		const Slicer &	slicer,
		Array< Float > &	fullArray,
		const Array< Float > &	partArray,
		Float	minVal,
		Float	maxVal
	)

private

Fill the array part into the full array and put it using the given min/max values.

◆ putPart()

void casacore::CompressFloat::putPart	(	rownr_t	rownr,
		const Slicer &	slicer,
		const Array< Float > &	array,
		Float	scale,
		Float	offset
	)

private

Put a part of an array in a row using given scale/offset values.

◆ putSlice()

virtual void casacore::CompressFloat::putSlice	(	rownr_t	rownr,
		const Slicer &	slicer,
		const Array< Float > &	array
	)

privatevirtual

Put into a section of the array in the given row.

This will scale and offset to the underlying array.

Reimplemented from casacore::BaseMappedArrayEngine< Float, Short >.

◆ registerClass()

static void casacore::CompressFloat::registerClass ( )

static

Register the class name and the static makeObject "constructor".

This will make the engine known to the table system.

◆ reopenRW()

virtual void casacore::CompressFloat::reopenRW ( )

privatevirtual

Reopen the engine for read/write access.

It makes the column writable if the underlying column is writable.

Reimplemented from casacore::DataManager.

◆ scaleColumnOnGet()

void casacore::CompressFloat::scaleColumnOnGet	(	Array< Float > &	array,
		const Array< Short > &	target
	)

private

Scale and/or offset target to array for the entire column.

When the scale and offset are fixed, it will do the entire array. Otherwise it iterates through the array and applies the scale and offset per row.

◆ scaleColumnOnPut()

void casacore::CompressFloat::scaleColumnOnPut	(	const Array< Float > &	array,
		Array< Short > &	target
	)

private

Scale and/or offset array to target for the entire column.

When the scale and offset are fixed, it will do the entire array. Otherwise it iterates through the array and applies the scale and offset per row.

◆ scaleOnGet()

void casacore::CompressFloat::scaleOnGet	(	Float	scale,
		Float	offset,
		Array< Float > &	array,
		const Array< Short > &	target
	)

private

Scale and/or offset target to array.

This is meant when reading an array from the stored column. It optimizes for scale=1 and/or offset=0.

◆ scaleOnPut()

void casacore::CompressFloat::scaleOnPut	(	Float	scale,
		Float	offset,
		const Array< Float > &	array,
		Array< Short > &	target
	)

private

Scale and/or offset array to target.

This is meant when writing an array into the stored column. It optimizes for scale=1 and/or offset=0.

Member Data Documentation

◆ autoScale_p

Bool casacore::CompressFloat::autoScale_p

private

Definition at line 314 of file CompressFloat.h.

◆ buffer_p

Array<Short> casacore::CompressFloat::buffer_p

private

Definition at line 317 of file CompressFloat.h.

◆ fixed_p

Bool casacore::CompressFloat::fixed_p

private

Definition at line 313 of file CompressFloat.h.

Referenced by getOffset(), and getScale().

◆ offset_p

Float casacore::CompressFloat::offset_p

private

Definition at line 312 of file CompressFloat.h.

Referenced by getOffset().

◆ offsetColumn_p

ScalarColumn<Float>* casacore::CompressFloat::offsetColumn_p

private

Definition at line 316 of file CompressFloat.h.

Referenced by getOffset().

◆ offsetName_p

String casacore::CompressFloat::offsetName_p

private

Definition at line 310 of file CompressFloat.h.

◆ scale_p

Float casacore::CompressFloat::scale_p

private

Definition at line 311 of file CompressFloat.h.

Referenced by getScale().

◆ scaleColumn_p

ScalarColumn<Float>* casacore::CompressFloat::scaleColumn_p

private

Definition at line 315 of file CompressFloat.h.

Referenced by getScale().

◆ scaleName_p

String casacore::CompressFloat::scaleName_p

private

Definition at line 309 of file CompressFloat.h.

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

tables/DataMan/CompressFloat.h

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Intended use:

Review Status

Prerequisite

Synopsis

Motivation

Example

Constructor & Destructor Documentation

◆ CompressFloat() [1/4]

◆ CompressFloat() [2/4]

◆ CompressFloat() [3/4]

◆ ~CompressFloat()

◆ CompressFloat() [4/4]

Member Function Documentation

◆ addRowInit()

◆ className()

◆ clone()

◆ create64()

◆ dataManagerName()

◆ dataManagerSpec()

◆ dataManagerType()

◆ findMinMax()

◆ getArray()

◆ getArrayColumn()

◆ getArrayColumnCells()

◆ getColumnSlice()

◆ getColumnSliceCells()

◆ getOffset()

◆ getScale()

◆ getSlice()

◆ makeObject()

◆ makeScaleOffset()

◆ operator=()

◆ prepare()

◆ putArray()

◆ putArrayColumn()

◆ putArrayColumnCells()

◆ putColumnSlice()

◆ putColumnSliceCells()

◆ putFullPart()

◆ putPart()

◆ putSlice()

◆ registerClass()

◆ reopenRW()

◆ scaleColumnOnGet()

◆ scaleColumnOnPut()

◆ scaleOnGet()

◆ scaleOnPut()

Member Data Documentation

◆ autoScale_p

◆ buffer_p

◆ fixed_p

◆ offset_p

◆ offsetColumn_p

◆ offsetName_p

◆ scale_p

◆ scaleColumn_p

◆ scaleName_p