A class that provides storage of channel or other data. More...

#include <QDaqDataBuffer.h>

Inheritance diagram for QDaqDataBuffer:

Collaboration diagram for QDaqDataBuffer:

Public Slots
void	clear ()
	Clear all data.

void	push (const QDaqVector &v)
	Append a new row of values. More...

QDaqVector	get (int i)
	Return the i-th QDaqBuffer.

Public Slots inherited from QDaqObject
QString	errorBacktrace (int maxItems=10) const
	Print a backtrace of recent errors in this QDaqObject.

QString	path () const
	Return the object's path in the QDaq tree. More...

QString	objectTree () const
	Output in a string the object hierarchy beneath this object.

QString	listProperties () const
	List the objects properties.

QString	listFunctions () const
	List the objects scriptable functions.

QDaqObject *	parent () const

QDaqObjectList	children () const
	Return a list of children of this object.

bool	hasChildren () const
	Returns true if the object has children.

QDaqObject *	appendChild (QDaqObject *obj)
	Adds a new child QDaqObject, as the last child and returns a pointer to it.

QDaqObject *	insertBefore (QDaqObject newobj, QDaqObject existingobj)
	Adds a new child QDaqObject, before an existing child and returns a pointer to it.

QDaqObject *	clone ()
	Clone a QDaqObject with its child objects.

QDaqObject *	removeChild (QDaqObject *obj)
	Remove a child and return a pointer to it.

QDaqObject *	replaceChild (QDaqObject newobj, QDaqObject oldobj)
	Replace a child and return a pointer to the old child.

QDaqObject *	findChild (const QString &name) const
	Find the first child QDaqObject with objectName equal to name.

Protected Member Functions
virtual void	writeh5 (H5::Group h5g, QDaqH5File f) const
	Write contents of the object to a H5 group. More...

virtual void	readh5 (H5::Group h5g, QDaqH5File f)
	Read contents of the object from a H5 group. More...

virtual bool	run ()
	Perform the QDaqDataBuffer tasks within a loop. More...

Protected Member Functions inherited from QDaqJob
virtual bool	arm_ ()
	Performs internal initialization for the job. More...

virtual void	disarm_ ()
	Performs internal de-initialization. More...

bool	setArmed (bool on)
	Arms or disarms a job. More...

virtual bool	exec ()
	Called when the job is executed. More...

Protected Member Functions inherited from QDaqObject
void	pushError (const QString &type, const QString &descr=QString()) const
	Push an error in the error queue.

void	throwScriptError (const QString &msg) const
	Throw a script error with message msg.

bool	checkName (const QString &name) const
	Check if name is a legal name for an QDaqObject. More...

Properties
uint	backBufferDepth
	Size of the back buffer in rows.

uint	capacity
	Total capacity (allocated memory) of the data buffer in rows.

uint	size
	Current size of the data buffer in rows.

uint	columns
	Number of data columns.

bool	circular
	True if buffer is circular.

QDaqObjectList	channels
	A QList of the channels monitored by this object.

QStringList	columnNames
	A list of column names.

Properties inherited from QDaqJob
bool	armed
	True if job is armed. More...

QString	runCode
	Script code executed by the job at each repetition. More...

QString	armCode
	Script code executed by the job in the arming face. More...

QString	disarmCode
	Script code executed by the job in the dis-arming face. More...

Additional Inherited Members
Signals inherited from QDaqObject
void	propertiesChanged ()
	Fired when object properties have changed.

void	updateWidgets ()
	Fired when widgets need update.

Public Member Functions inherited from QDaqJob
Q_INVOKABLE	QDaqJob (const QString &name)
	QDaqJob constructor. More...

virtual void	attach ()
	Attach this QDaqObject to the QDaq tree. More...

virtual void	detach ()
	Detach this QDaqObject from the QDaq tree. More...

QDaqLoop *	topLoop () const
	Returns the top level loop that this job belongs to.

QDaqLoop *	loop () const
	Returns the loop that this job belongs to.

virtual QDaqScriptEngine *	loopEngine () const
	Returns the QDaqScriptEngine of the top level loop.

Public Member Functions inherited from QDaqObject
Q_INVOKABLE	QDaqObject (const QString &name)
	Construct a QDaqObject with a name. More...

bool	isAttached () const
	Returns true is this object is attached to the QDaq tree.

Static Public Member Functions inherited from QDaqObject
static QDaqRoot *	root ()
	Obtain a pointer to the one-and-only QDaqRoot object.

static QDaqObject *	fromPath (const QString &path)
	Return a pointer to an object given its full path in the QDaq tree. More...

Public Attributes inherited from QDaqObject
QMutex	comm_lock
	A recursive mutex for synching thread access to this object.

Detailed Description

A class that provides storage of channel or other data.

If QDaqDataBuffer is used within a QDaqLoop then at each repetition it will store the values of all channels that have been assigned to it. The data are stored internally as a matrix of QDaqBuffer objects, keeping one QDaqBuffer per channel. A new row of data is added at each loop repetition.

QDaqDataBuffer has an internal back buffer, where data generated in the loop thread are initially stored. The data is later transferred to the main buffer whenever possible and becomes available to the main application thread. The process is marshalled internally by a semaphore and the Qt signal/slot mechanism. Increasing the size of the back buffer can prevent data loss in fast loops.

The QDaqDataBuffer may be also used as a static object outside of a loop. Data may be appended by the push() function.

Definition at line 34 of file QDaqDataBuffer.h.

Member Function Documentation

void QDaqDataBuffer::push ( const QDaqVector & v )

slot

Append a new row of values.

Parameters

v	Vector of data values. v.size() must be equal to size().

Definition at line 357 of file QDaqDataBuffer.cpp.

void QDaqDataBuffer::readh5	(	H5::Group *	g,
		QDaqH5File *	f
	)

protectedvirtual

Read contents of the object from a H5 group.

The base class implementation reads all properties (static & dynamic) from corresponding datasets of the HDF5 file group.

Reimplement in QDaqObject descendants to read additional data.

Parameters

g	HDF5 Group object

Reimplemented from QDaqObject.

Definition at line 46 of file QDaqH5Serialize.cpp.

bool QDaqDataBuffer::run ( )

protectedvirtual

Perform the QDaqDataBuffer tasks within a loop.

The following tasks are performed at each loop repetition

the object tries to acquire a free back buffer packet
If succesfull it fills the packet with data from the assigned channels and signals the main thread to collect the packet.
otherwise it pushes a QDaq error that data got lost

Returns: QDaqJob::run()

Reimplemented from QDaqJob.

Definition at line 251 of file QDaqDataBuffer.cpp.

void QDaqDataBuffer::writeh5	(	H5::Group *	g,
		QDaqH5File *	f
	)		const

protectedvirtual

Write contents of the object to a H5 group.

The base class implementation writes all properties (static & dynamic) as datasets of the HDF5 file group.

Reimplement in QDaqObject descendants to write additional data.

Parameters

g	HDF5 Group object

Reimplemented from QDaqObject.

Definition at line 22 of file QDaqH5Serialize.cpp.

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

/home/george/Dev/rtlab/qdaq/lib/core/QDaqDataBuffer.h
/home/george/Dev/rtlab/qdaq/lib/core/QDaqDataBuffer.cpp
/home/george/Dev/rtlab/qdaq/lib/core/QDaqH5Serialize.cpp

Public Slots

Protected Member Functions

Properties

Additional Inherited Members

Detailed Description

Member Function Documentation