TiledCellStMan.h

Classes

TiledCellStMan -- Tiled Cell Storage Manager. (full description)

class TiledCellStMan : public TiledStMan

Interface

Public Members
TiledCellStMan (const String& hypercolumnName, const IPosition& defaultTileShape, uInt maximumCacheSize = 0)
TiledCellStMan (const String& hypercolumnName, const Record& spec)
~TiledCellStMan()
DataManager* clone() const
String dataManagerType() const
Bool canChangeShape() const
virtual void setShape (uInt rownr, TSMCube* hypercube, const IPosition& shape, const IPosition& tileShape)
static DataManager* makeObject (const String& dataManagerType, const Record& spec)
Private Members
TiledCellStMan()
TiledCellStMan (const TiledCellStMan&)
TiledCellStMan& operator= (const TiledCellStMan&)
virtual IPosition defaultTileShape() const
void addRow (uInt nrrow)
virtual TSMCube* getHypercube (uInt rownr)
virtual TSMCube* getHypercube (uInt rownr, IPosition& position)
virtual void setupCheck (const TableDesc& tableDesc, const Vector<String>& dataNames) const
virtual Bool flush (AipsIO&, Bool fsync)
virtual void create (uInt nrrow)
virtual void readHeader (uInt nrrow, Bool firstTime)

Description

Review Status

Reviewed By:
UNKNOWN
Date Reviewed:
before2004/08/25

Prerequisite

Etymology

TiledCellStMan is the Tiled Storage Manager storing each cell as a separate hypercube.

Synopsis

TiledCellStMan is a derivation from TiledStMan, the abstract tiled storage manager class. A description of the basics of tiled storage managers is given in the Tables module description.

TiledCellStMan allows the user to create a tiled hypercube for each data cell in an automatic way. It is meant to be used for storing regularly shaped data like images (where the table contains a possibly differently shaped image in each row).

The TiledCellStMan has the following (extra) properties:

Motivation

This tiled storage manager does not require any special action (like calling add/extendHypercube) when used with a column containing variable shaped arrays.

Example

  // Define the table description and the columns in it.
  TableDesc td ("", "1", TableDesc::Scratch);
  td.addColumn (ArrayColumnDesc<float>  ("RA", 1));
  td.addColumn (ArrayColumnDesc<float>  ("Dec", 1));
  td.addColumn (ArrayColumnDesc<float>  ("Velocity", 1));
  td.addColumn (ArrayColumnDesc<float>  ("Image", 3));
  // Define the 3-dim hypercolumn with its data and coordinate columns.
  // Note that its dimensionality must match the dimensionality
  // of the data cells.
  td.defineHypercolumn ("TSMExample",
			  3,
			  stringToVector ("Image"),
			  stringToVector ("RA,Dec,Velocity"));
  // Now create a new table from the description.
  SetupNewTable newtab("tTiledCellStMan_tmp.data", td, Table::New);
  // Create a TiledCellStMan storage manager for the hypercolumn
  // and bind the columns to it.
  TiledCellStMan sm1 ("TSMExample");
  newtab.bindAll (sm1);
  // Create the table.
  Table table(newtab);
  // Define the values for the coordinates of the hypercube.
  Vector<float> raValues(512);
  Vector<float> DecValues(512);
  Vector<float> VelocityValues(64);
  indgen (raValues);
  indgen (decValues, float(100));
  indgen (velocityValues, float(200));
  ArrayColumn<float> ra (table, "RA");
  ArrayColumn<float> dec (table, "Dec");
  ArrayColumn<float> velocity (table, "Velocity");
  ArrayColumn<float> image (table, "Image");
  Cube<float> imageValues(IPosition(3,512,512,64));
  indgen (imageValues);
  // Write some data into the data columns.
  uInt i;
  for (i=0; i<4; i++) {
      table.addRow();
	image.put (i, imageValues);
      ra.put (i, raValues);
      dec.put (i, decValues);
      velocity.put (i, velocityValues);
  }

Member Description

TiledCellStMan (const String& hypercolumnName, const IPosition& defaultTileShape, uInt maximumCacheSize = 0)
TiledCellStMan (const String& hypercolumnName, const Record& spec)

Create a TiledDataStMan storage manager for the hypercolumn with the given name. The columns used should have the FixedShape attribute set. The hypercolumn name is also the name of the storage manager. The given tile shape will be used as the default for the hypercube in each cell. Per cell it can be redefined via ArrayColumn::setShape. The given maximum cache size (default is unlimited) is persistent, thus will be reused when the table is read back. Note that the class ROTiledStManAccessor allows one to overwrite the maximum cache size temporarily. Its description contains a discussion about the effects of setting a maximum cache.
The constructor taking a Record expects fields in the record with the name of the arguments in uppercase. If not defined, their default value is used.

~TiledCellStMan()

DataManager* clone() const

Clone this object. It does not clone TSMColumn objects possibly used.

String dataManagerType() const

Get the type name of the data manager (i.e. TiledCellStMan).

Bool canChangeShape() const

This tiled storage manager can handle changing array shapes.

virtual void setShape (uInt rownr, TSMCube* hypercube, const IPosition& shape, const IPosition& tileShape)

Set the shape and tile shape of the hypercube.

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

Make the object from the type name string. This function gets registered in the DataManager "constructor" map.

TiledCellStMan()

Create a TiledCellStMan. This constructor is private, because it should only be used by makeObject.

TiledCellStMan (const TiledCellStMan&)

Forbid copy constructor.

TiledCellStMan& operator= (const TiledCellStMan&)

Forbid assignment.

virtual IPosition defaultTileShape() const

Get the default tile shape.

void addRow (uInt nrrow)

Add rows to the storage manager.

virtual TSMCube* getHypercube (uInt rownr)

Get the hypercube in which the given row is stored.

virtual TSMCube* getHypercube (uInt rownr, IPosition& position)

Get the hypercube in which the given row is stored. It also returns the position of the row in that hypercube.

virtual void setupCheck (const TableDesc& tableDesc, const Vector<String>& dataNames) const

Check if the hypercolumn definition fits this storage manager.

virtual Bool flush (AipsIO&, Bool fsync)

Flush and optionally fsync the data. It returns a True status if it had to flush (i.e. if data have changed).

virtual void create (uInt nrrow)

Let the storage manager create files as needed for a new table. This allows a column with an indirect array to create its file.

virtual void readHeader (uInt nrrow, Bool firstTime)

Read the header info.