this represents one chunk of memory which can represent one or more columns of data for JKQTBasePlotter. See JKQTPDatastore for more information. More...

#include <jkqtpdatastorage.h>

Public Member Functions
	JKQTPDatastoreItem (const QVector< double > &data)
	class constructor: initializes the object for internal data storage with the given data

	JKQTPDatastoreItem (JKQTPDatastoreItemFormat dataformat, double *data, size_t columns, size_t rows)
	class constructor: initializes the object for external data storage

	JKQTPDatastoreItem (JKQTPDatastoreItemFormat dataformat, double *data, size_t columns, size_t rows, bool storageType)
	class constructor: initializes the object for external data storage

	JKQTPDatastoreItem (size_t columns, size_t rows)
	class constructor: initializes the object for internal data storage

	~JKQTPDatastoreItem ()
	class destructor: frees unfreed internal memory

bool	append (size_t column, const QVector< double > &values)
	adds new rows to the given column. Returns `true` on success and `false` else

bool	append (size_t column, const std::vector< double > &values)
	adds new rows to the given column. Returns `true` on success and `false` else

bool	append (size_t column, double value)
	adds a new row to the given column. Returns `true` on success and `false` else

double &	at (size_t column, size_t row)
	returns a reference to the data at the position (column, row ). Throws an exception when the entry does not exist!

const double &	at (size_t column, size_t row) const
	returns a const reference to the data at the position (column, row ). Throws an exception when the entry does not exist!

void	erase (size_t row)
	if `isValid()` : erase the row row

void	erase (size_t row, size_t rowEnd)
	if `isValid()` : erase all rows (and including) from row to rowEnd

double	get (size_t column, size_t row)
	returns the data at the position (column, row ).

size_t	getColumns () const
	as data may also point to a matrix, this specifies the number of columns in this element (default: 1)

double *	getPointer (size_t column, size_t row)
	returns the data at the position (column, row ). The column index specifies the column inside THIS item, not the global column number.

const double *	getPointer (size_t column, size_t row) const
	returns the data at the position (column, row ). The column index specifies the column inside THIS item, not the global column number.

size_t	getRows () const
	number of rows in this item

bool	isVector () const
	checks whether dataformat==JKQTPDatastoreItemFormat::SingleColumn and storageType==StorageType::Vector

bool	push_back (size_t column, double value)
	adds a new row to the given column. Returns `true` on success and `false` else

void	resize (size_t rows_new)
	if `isValid()` : resize the row to have rows_new rows

bool	resizeColumns (size_t rows)
	change the size of all columns to the givne number of rows. Returns `true` if the old data could be retained/saved and `false` if the old data was lost (which happens in most of the cases!)

void	set (size_t column, size_t row, double value)
	set the data at the position (column, row ) to value. The column index specifies the column inside THIS item, not the global column number.

Protected Member Functions
	JKQTPDatastoreItem ()
	hidden default constructor

Private Types
enum class	StorageType { Internal , External , Vector }
	how data is represented in this JKQTPDatastoreItem More...

Private Attributes
bool	allocated
	Specifies whether memory for the data has been allocated. This is only used, when `internal==true`.

size_t	columns
	as data may also point to a matrix, this specifies the number of columns in this element (default: 1)

double *	data
	a pointer to the actual data

JKQTPDatastoreItemFormat	dataformat
	memory format of the data in this item

QVector< double >	datavec
	iif storageType is `StorageType::Vector`, the data is actually save here and data contains a pointer to the data in datavec

size_t	rows
	number of rows in this item

StorageType	storageType
	specifies whether the datastore manages the memory (`true` ) or whether the user application does this (`false` ) .

Detailed Description

this represents one chunk of memory which can represent one or more columns of data for JKQTBasePlotter. See JKQTPDatastore for more information.

Each chunk of memory is pointed at by a simple double* pointer data. the memory layout of the memory layout of the RAM segment pointed at by data is determined by the parameter dataformat:

the types of data in one JKQTdatastoreItem

JKQTPSingleColumn:

+-----+-----+-----+....................+-----+
|  0  |  1  |  2  |                    + N-1 |
+-----+-----+-----+....................+-----+

JKQTPMatrixColumn:

 ================= COLUMN 1 =================  ================= COLUMN 2 =================
+-----+-----+-----+....................+-----++-----+-----+-----+....................+-----+ .....
|  0  |  1  |  2  |                    + N-1 ||  0  |  1  |  2  |                    + N-1 |
+-----+-----+-----+....................+-----++-----+-----+-----+....................+-----+ .....
 =R1== =R2== =R3==                      =RN==  =R1== =R2== =R3==                      =RN==

JKQTPMatrixRow (C standard representation of matrices):

 ================== ROW  1 ==================  ================== ROW  2 ==================
+-----+-----+-----+....................+-----++-----+-----+-----+....................+-----+ .....
|  0  |  1  |  2  |                    + N-1 ||  0  |  1  |  2  |                    + N-1 |
+-----+-----+-----+....................+-----++-----+-----+-----+....................+-----+ .....
 =C1== =C2== =C3==                      =CN==  =C1== =C2== =C3==                      =CN==

The properties columns and rows determine how many columns and rows are represented by this item (access via getColumns() and getRows() ). This class may manage chunks of "internal" and "external" memory (which is indicated by the boolean property internal. Internal memory will be allocated (in the constructor) and freed (in the destructor) by this object. External memory may be accessed via this class, but will neither by allocated nor freed. These tasks are up to the user. Use this option, if you don't want to generate copies of huge datasets, or you want to change the data while the program is running and don't want to do the change at more than one spot.

you can use get() and set() to access the memory chunc.

See also: JKQTPDatastore

Member Enumeration Documentation

◆ StorageType

enum class JKQTPDatastoreItem::StorageType

strongprivate

how data is represented in this JKQTPDatastoreItem

Enumerator
Internal	data is stored in an internally managed (=owned, i.e. freed in the destructor) C-array
External	data is stored in an externally managed (=not owned) C-array
Vector	data is stored in the internal QVector<double> datavec

Constructor & Destructor Documentation

◆ JKQTPDatastoreItem() [1/5]

JKQTPDatastoreItem::JKQTPDatastoreItem ( )

protected

hidden default constructor

◆ JKQTPDatastoreItem() [2/5]

JKQTPDatastoreItem::JKQTPDatastoreItem	(	size_t	columns,
		size_t	rows
	)

class constructor: initializes the object for internal data storage

◆ JKQTPDatastoreItem() [3/5]

JKQTPDatastoreItem::JKQTPDatastoreItem ( const QVector< double > & data )

class constructor: initializes the object for internal data storage with the given data

◆ JKQTPDatastoreItem() [4/5]

JKQTPDatastoreItem::JKQTPDatastoreItem	(	JKQTPDatastoreItemFormat	dataformat,
		double *	data,
		size_t	columns,
		size_t	rows
	)

class constructor: initializes the object for external data storage

◆ JKQTPDatastoreItem() [5/5]

JKQTPDatastoreItem::JKQTPDatastoreItem	(	JKQTPDatastoreItemFormat	dataformat,
		double *	data,
		size_t	columns,
		size_t	rows,
		bool	storageType
	)

class constructor: initializes the object for external data storage

◆ ~JKQTPDatastoreItem()

JKQTPDatastoreItem::~JKQTPDatastoreItem ( )

class destructor: frees unfreed internal memory

Member Function Documentation

◆ append() [1/3]

bool JKQTPDatastoreItem::append	(	size_t	column,
		const QVector< double > &	values
	)

inline

adds new rows to the given column. Returns true on success and false else

This operation is currently only possible, if storageType==StorageType::Vector !

◆ append() [2/3]

bool JKQTPDatastoreItem::append	(	size_t	column,
		const std::vector< double > &	values
	)

inline

adds new rows to the given column. Returns true on success and false else

This operation is currently only possible, if storageType==StorageType::Vector !

◆ append() [3/3]

bool JKQTPDatastoreItem::append	(	size_t	column,
		double	value
	)

inline

adds a new row to the given column. Returns true on success and false else

This operation is currently only possible, if storageType==StorageType::Vector !

◆ at() [1/2]

double & JKQTPDatastoreItem::at	(	size_t	column,
		size_t	row
	)

inline

returns a reference to the data at the position (column, row ). Throws an exception when the entry does not exist!

Note: The column index specifies the column inside THIS item, not the global column number.

◆ at() [2/2]

const double & JKQTPDatastoreItem::at	(	size_t	column,
		size_t	row
	)		const

inline

returns a const reference to the data at the position (column, row ). Throws an exception when the entry does not exist!

Note: The column index specifies the column inside THIS item, not the global column number.

◆ erase() [1/2]

void JKQTPDatastoreItem::erase ( size_t row )

inline

if isValid() : erase the row row

◆ erase() [2/2]

void JKQTPDatastoreItem::erase	(	size_t	row,
		size_t	rowEnd
	)

inline

if isValid() : erase all rows (and including) from row to rowEnd

◆ get()

double JKQTPDatastoreItem::get	(	size_t	column,
		size_t	row
	)

inline

returns the data at the position (column, row ).

Note: The column index specifies the column inside THIS item, not the global column number.

◆ getColumns()

size_t JKQTPDatastoreItem::getColumns ( ) const

inline

as data may also point to a matrix, this specifies the number of columns in this element (default: 1)

◆ getPointer() [1/2]

double * JKQTPDatastoreItem::getPointer	(	size_t	column,
		size_t	row
	)

inline

returns the data at the position (column, row ). The column index specifies the column inside THIS item, not the global column number.

◆ getPointer() [2/2]

const double * JKQTPDatastoreItem::getPointer	(	size_t	column,
		size_t	row
	)		const

inline

returns the data at the position (column, row ). The column index specifies the column inside THIS item, not the global column number.

◆ getRows()

size_t JKQTPDatastoreItem::getRows ( ) const

inline

number of rows in this item

◆ isVector()

bool JKQTPDatastoreItem::isVector ( ) const

inline

checks whether dataformat==JKQTPDatastoreItemFormat::SingleColumn and storageType==StorageType::Vector

◆ push_back()

bool JKQTPDatastoreItem::push_back	(	size_t	column,
		double	value
	)

inline

adds a new row to the given column. Returns true on success and false else

This operation is currently only possible, if storageType==StorageType::Vector !

◆ resize()

void JKQTPDatastoreItem::resize ( size_t rows_new )

inline

if isValid() : resize the row to have rows_new rows

◆ resizeColumns()

bool JKQTPDatastoreItem::resizeColumns ( size_t rows )

change the size of all columns to the givne number of rows. Returns true if the old data could be retained/saved and false if the old data was lost (which happens in most of the cases!)

◆ set()

void JKQTPDatastoreItem::set	(	size_t	column,
		size_t	row,
		double	value
	)

inline

set the data at the position (column, row ) to value. The column index specifies the column inside THIS item, not the global column number.

Member Data Documentation

◆ allocated

bool JKQTPDatastoreItem::allocated

private

Specifies whether memory for the data has been allocated. This is only used, when internal==true.

◆ columns

size_t JKQTPDatastoreItem::columns

private

as data may also point to a matrix, this specifies the number of columns in this element (default: 1)

◆ data

double* JKQTPDatastoreItem::data

private

a pointer to the actual data

◆ dataformat

JKQTPDatastoreItemFormat JKQTPDatastoreItem::dataformat

private

memory format of the data in this item

◆ datavec

QVector<double> JKQTPDatastoreItem::datavec

private

iif storageType is StorageType::Vector, the data is actually save here and data contains a pointer to the data in datavec

◆ rows

size_t JKQTPDatastoreItem::rows

private

number of rows in this item

◆ storageType

StorageType JKQTPDatastoreItem::storageType

private

specifies whether the datastore manages the memory (true ) or whether the user application does this (false ) .

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

jkqtpdatastorage.h

Public Member Functions

Protected Member Functions

Private Types

Private Attributes

Detailed Description

Member Enumeration Documentation

◆ StorageType

Constructor & Destructor Documentation

◆ JKQTPDatastoreItem() [1/5]

◆ JKQTPDatastoreItem() [2/5]

◆ JKQTPDatastoreItem() [3/5]

◆ JKQTPDatastoreItem() [4/5]

◆ JKQTPDatastoreItem() [5/5]

◆ ~JKQTPDatastoreItem()

Member Function Documentation

◆ append() [1/3]

◆ append() [2/3]

◆ append() [3/3]

◆ at() [1/2]

◆ at() [2/2]

◆ erase() [1/2]

◆ erase() [2/2]

◆ get()

◆ getColumns()

◆ getPointer() [1/2]

◆ getPointer() [2/2]

◆ getRows()

◆ isVector()

◆ push_back()

◆ resize()

◆ resizeColumns()

◆ set()

Member Data Documentation

◆ allocated

◆ columns

◆ data

◆ dataformat

◆ datavec

◆ rows

◆ storageType