SeqAcqEPI Class Reference
[Classes for sequence design (odinseq library)]

Acquisition + echo-planar imaging readout. More...

#include <seqacqepi.h>

Inheritance diagram for SeqAcqEPI:

[legend]Collaboration diagram for SeqAcqEPI:

[legend]List of all members.

Public Member Functions
	SeqAcqEPI (const STD_string &object_label, double sweepwidth, unsigned int read_size, float FOVread, unsigned int phase_size, float FOVphase, unsigned int shots=1, unsigned int reduction=1, float gradshift=0.0, const STD_string &nucleus="", const dvector &phaselist=0, const dvector &freqlist=0, rampType rampmode=linear, bool ramp_sampling=false, float ramp_steepness=1.0, float fourier_factor=0.0, unsigned int echo_pairs=0)
	SeqAcqEPI (const SeqAcqEPI &sae)
	SeqAcqEPI (const STD_string &object_label="unnamedSeqAcqEPI")
	~SeqAcqEPI ()
unsigned int	get_npts_read () const
unsigned int	get_numof_gradechoes () const
fvector	get_readout_shape () const
SeqAcqEPI &	set_gradrotmatrixvector (const SeqRotMatrixVector &matrixVec)
SeqAcqEPI &	invert_readstrength ()
SeqAcqEPI &	set_phaseoff ()
SeqAcqEPI &	operator= (const SeqAcqEPI &sae)
double	get_acquisition_center () const
double	get_acquisition_start () const
unsigned int	get_npts () const
float	get_oversampling () const
SeqAcqInterface &	set_oversampling (float os_factor)
SeqAcqInterface &	set_template_type (templateType type)
SeqAcqInterface &	set_reco_vector (recoDim dim, const SeqVector &vec, const dvector &valvec=dvector())
SeqAcqInterface &	set_default_reco_index (recoDim dim, unsigned int index)
const SeqVector *	get_dephgrad (SeqGradChanParallel &dephobj, bool rephase) const
SeqFreqChanInterface &	set_nucleus (const STD_string &nucleus)
SeqFreqChanInterface &	set_freqlist (const dvector &freqlist)
SeqFreqChanInterface &	set_phaselist (const dvector &phaselist)
const SeqVector &	get_phaselist_vector () const
const SeqVector &	get_freqlist_vector () const
SeqFreqChanInterface &	set_reorder_scheme (reorderScheme scheme, unsigned int nsegments=1)
SeqFreqChanInterface &	set_encoding_scheme (encodingScheme scheme)
const SeqVector &	get_reorder_vector () const
SeqGradInterface &	set_strength (float gradstrength)
SeqGradInterface &	invert_strength ()
float	get_strength () const
fvector	get_gradintegral () const
double	get_gradduration () const
SeqGradInterface &	set_gradrotmatrix (const RotMatrix &matrix)
STD_string	get_program (programContext &context) const
double	get_duration () const
SeqValList	get_freqvallist (freqlistAction action) const
void	query (queryContext &context) const
RecoValList	get_recovallist (unsigned int reptimes, JDXkSpaceCoords &coords) const
bool	contains (const SeqTreeObj *sto) const
bool	contains (objCategory cat) const
void	tree (SeqTreeCallbackAbstract *display) const
unsigned int	event (eventContext &context) const
STD_string	get_properties () const

---

Detailed Description

Acquisition + echo-planar imaging readout.

This class represents an acquisition window with an EPI gradient.

Definition at line 200 of file seqacqepi.h.

---

Constructor & Destructor Documentation

SeqAcqEPI::SeqAcqEPI	(	const STD_string &	object_label,
		double	sweepwidth,
		unsigned int	read_size,
		float	FOVread,
		unsigned int	phase_size,
		float	FOVphase,
		unsigned int	shots = 1,
		unsigned int	reduction = 1,
		float	gradshift = 0.0,
		const STD_string &	nucleus = "",
		const dvector &	phaselist = 0,
		const dvector &	freqlist = 0,
		rampType	rampmode = linear,
		bool	ramp_sampling = false,
		float	ramp_steepness = 1.0,
		float	fourier_factor = 0.0,
		unsigned int	echo_pairs = 0
	)

Constructs an acquisition window with an EPI gradient labeled 'object_label' with the following properties:

• sweepwidth: The sampling frequency
• read_size: The number of sampling points per gradient echo, with ramp_sampling enabled, this is the number of points after regridding
• FOVread: The Field Of View in read direction
• phase_size: The final matrix size in phase direction without partial fourier undersampling
• FOVphase: The Field Of View in phase direction
• shots: Number of shots, a multi-shot (segmented) EPI readout will be created if 'shots' is larger than 1
• reduction: Reduction factor (parallel imaging)
• gradshift: An additional delay to fine-tune the time shift between the gradient and acquisition channel
• nucleus: The nucleus to measure
• phaselist: Phase list for acquisition
• freqlist: Frequency list for acquisition
• rampmode: This parameter determines the shape of the ramp waveform
• ramp_sampling: The EPI readout performs data acquisition during the ramps if this parameter is set to 'true'
• ramp_steepness: This parameter in the range of ]0,1] determines the relative rising speed of the gradient strength, i.e. with 1 the gradients are switched as fast as possible
• fourier_factor: The amount of undersampling (0=no undersampling, 1=half fourier)
• echo_pairs: Number of interleaved acquired pairs of echoes for one phase-encodin step, 0 means only one echo

SeqAcqEPI::SeqAcqEPI

(

const SeqAcqEPI &

sae

)

Constructs an acquisition window with an EPI gradient which is a copy of 'sae'

SeqAcqEPI::SeqAcqEPI

(

const STD_string &

object_label = "unnamedSeqAcqEPI"

)

Constructs an empty acquisition window with an EPI gradient with the given label.

SeqAcqEPI::~SeqAcqEPI

(

)

Destructor

---

Member Function Documentation

unsigned int SeqAcqEPI::get_npts_read

(

)

const [inline]

Returns the number of points that will be acquired during each read gradient period, including the ramp points.

Definition at line 255 of file seqacqepi.h.

unsigned int SeqAcqEPI::get_numof_gradechoes

(

)

const [inline]

Returns the number of gradient echoes, i.e. the number of k-space lines that will be sampled

Definition at line 261 of file seqacqepi.h.

fvector SeqAcqEPI::get_readout_shape

(

)

const [inline]

Returns the readout gradient shape that is used for regridding

Definition at line 266 of file seqacqepi.h.

SeqAcqEPI& SeqAcqEPI::set_gradrotmatrixvector

(

const SeqRotMatrixVector &

matrixVec

)

[inline]

Specifies an extra vector of rotatition matrices to be used with this block of the sequence. The sequence vector 'matrixVec' can then be attached to a loop to iterate over the different matrices.

Definition at line 273 of file seqacqepi.h.

SeqAcqEPI& SeqAcqEPI::invert_readstrength

(

)

[inline]

Inverts the polarity of the readout gradients, leaves the phaseblips untouched

Definition at line 278 of file seqacqepi.h.

SeqAcqEPI& SeqAcqEPI::set_phaseoff

(

)

[inline]

Sets the strength of the phaseblips to zero

Definition at line 283 of file seqacqepi.h.

SeqAcqEPI& SeqAcqEPI::operator=

(

const SeqAcqEPI &

sae

)

This assignment operator will make this object become an exact copy of 'sae'.

double SeqAcqEPI::get_acquisition_center

(

)

const [inline, virtual]

Returns the the duration from the the beginnig of the acquisition object to the middle of the acquisition window.

Reimplemented from SeqAcqInterface.

Definition at line 299 of file seqacqepi.h.

double SeqAcqEPI::get_acquisition_start

(

)

const [inline, virtual]

Returns the the duration from the the beginnig of the acquisition object to the beginnig of the acquisition window (the point of time where data starts to be acquired).

Reimplemented from SeqAcqInterface.

Definition at line 300 of file seqacqepi.h.

unsigned int SeqAcqEPI::get_npts

(

)

const [inline, virtual]

Returns the total number of sampling points, without oversampling

Reimplemented from SeqAcqInterface.

Definition at line 301 of file seqacqepi.h.

float SeqAcqEPI::get_oversampling

(

)

const [inline, virtual]

Returns the oversampling factor

Reimplemented from SeqAcqInterface.

Definition at line 302 of file seqacqepi.h.

SeqAcqInterface& SeqAcqEPI::set_oversampling

(

float

os_factor

)

[inline, virtual]

Sets the oversampling factor for this acquisition object, os_factor=1 means no oversampling.

Reimplemented from SeqAcqInterface.

Definition at line 303 of file seqacqepi.h.

SeqAcqInterface& SeqAcqEPI::set_template_type

(

templateType

type

)

[virtual]

Sets the template mode of this acquisition object. This is also relevant for automatic reconstruction.

Reimplemented from SeqAcqInterface.

SeqAcqInterface& SeqAcqEPI::set_reco_vector	(	recoDim	dim,
		const SeqVector &	vec,
		const dvector &	valvec = dvector()
	)			[inline, virtual]

Specifies a vector 'vec' which indexes the data dimension 'dim'. The current index for each acquisition is retrieved from the vector. This is relevant for automatic reconstruction. An additional vector 'valvec' of double values can be given, which is attached to this dimension, e.g. different TEs in the echo dimension.

Reimplemented from SeqAcqInterface.

Definition at line 305 of file seqacqepi.h.

SeqAcqInterface& SeqAcqEPI::set_default_reco_index	(	recoDim	dim,
		unsigned int	index
	)			[inline, virtual]

Sets the default value 'index' for the reco index in dimension 'dim'. This is relevant for automatic reconstruction.

Reimplemented from SeqAcqInterface.

Definition at line 306 of file seqacqepi.h.

const SeqVector* SeqAcqEPI::get_dephgrad	(	SeqGradChanParallel &	dephobj,
		bool	rephase
	)			const [virtual]

to be used by SeqAcqDeph to retrieve pre-dephasing gradients from acquisition object. Overload this function if your acq needs pre-dephasers, return them by appending them to 'dephobj'. Returns any possible vector object as the return value.

Reimplemented from SeqAcqInterface.

SeqFreqChanInterface& SeqAcqEPI::set_nucleus

(

const STD_string &

nucleus

)

[inline, virtual]

Specify the nucleus for this frequency channel

Reimplemented from SeqFreqChanInterface.

Definition at line 310 of file seqacqepi.h.

SeqFreqChanInterface& SeqAcqEPI::set_freqlist

(

const dvector &

freqlist

)

[inline, virtual]

Sets the freqlist for the object

Reimplemented from SeqFreqChanInterface.

Definition at line 311 of file seqacqepi.h.

SeqFreqChanInterface& SeqAcqEPI::set_phaselist

(

const dvector &

phaselist

)

[inline, virtual]

Sets the phaselist for the object

Reimplemented from SeqFreqChanInterface.

Definition at line 312 of file seqacqepi.h.

const SeqVector& SeqAcqEPI::get_phaselist_vector

(

)

const [inline, virtual]

Returns the phaselist vector (for loop insertion)

Reimplemented from SeqFreqChanInterface.

Definition at line 313 of file seqacqepi.h.

const SeqVector& SeqAcqEPI::get_freqlist_vector

(

)

const [inline, virtual]

Returns the frequency list vector (for loop insertion)

Reimplemented from SeqFreqChanInterface.

Definition at line 314 of file seqacqepi.h.

SeqFreqChanInterface& SeqAcqEPI::set_reorder_scheme	(	reorderScheme	scheme,
		unsigned int	nsegments = 1
	)			[inline, virtual]

Sets the reordering scheme for the frequency list

Reimplemented from SeqFreqChanInterface.

Definition at line 315 of file seqacqepi.h.

SeqFreqChanInterface& SeqAcqEPI::set_encoding_scheme

(

encodingScheme

scheme

)

[inline, virtual]

Sets the encoding scheme

Reimplemented from SeqFreqChanInterface.

Definition at line 316 of file seqacqepi.h.

const SeqVector& SeqAcqEPI::get_reorder_vector

(

)

const [inline, virtual]

Returns the reordering vector (for loop insertion)

Reimplemented from SeqFreqChanInterface.

Definition at line 317 of file seqacqepi.h.

SeqGradInterface& SeqAcqEPI::set_strength

(

float

gradstrength

)

[inline, virtual]

Changes the strength of the gradient object

Implements SeqGradInterface.

Definition at line 320 of file seqacqepi.h.

SeqGradInterface& SeqAcqEPI::invert_strength

(

)

[inline, virtual]

Changes the polarity of the gradient, i.e. inverts the sign of the gradient strength

Implements SeqGradInterface.

Definition at line 321 of file seqacqepi.h.

float SeqAcqEPI::get_strength

(

)

const [inline, virtual]

Returns the strength of the gradient object

Implements SeqGradInterface.

Definition at line 322 of file seqacqepi.h.

fvector SeqAcqEPI::get_gradintegral

(

)

const [inline, virtual]

Returns the integral vector of the gradient course

Implements SeqGradInterface.

Definition at line 323 of file seqacqepi.h.

double SeqAcqEPI::get_gradduration

(

)

const [inline, virtual]

Returns the duration of the gradient object. This function returns only the effective duration during whichthe gradient is active, any delays before and after the gradient are omitted.

Implements SeqGradInterface.

Definition at line 324 of file seqacqepi.h.

SeqGradInterface& SeqAcqEPI::set_gradrotmatrix

(

const RotMatrix &

matrix

)

[inline, virtual]

This function can be used to specify a rotation of the gradient object in the spatial domain, the rotation will be applied to this object only rather than to the whole sequence.

Implements SeqGradInterface.

Definition at line 325 of file seqacqepi.h.

STD_string SeqAcqEPI::get_program

(

programContext &

context

)

const [inline, virtual]

Returns the part in the pulse/gradient program of this sequence object. 'context' holds data about how the program should be generated, e.g. type of program and formatting.

Reimplemented from SeqTreeObj.

Definition at line 329 of file seqacqepi.h.

double SeqAcqEPI::get_duration

(

)

const [inline, virtual]

Returns the duration of the sequence object.

Implements SeqTreeObj.

Definition at line 330 of file seqacqepi.h.

SeqValList SeqAcqEPI::get_freqvallist

(

freqlistAction

action

)

const [inline, virtual]

Returns the list of frequency values in the objects branch of the sequence tree

Reimplemented from SeqTreeObj.

Definition at line 331 of file seqacqepi.h.

void SeqAcqEPI::query

(

queryContext &

context

)

const [inline, virtual]

Query the sequence tree recursively

Reimplemented from SeqTreeObj.

Definition at line 332 of file seqacqepi.h.

RecoValList SeqAcqEPI::get_recovallist	(	unsigned int	reptimes,
		JDXkSpaceCoords &	coords
	)			const [virtual]

Appends the k-space coordinates in this branch of the sequence tree to 'coords' and returns their ordering

Reimplemented from SeqTreeObj.

bool SeqAcqEPI::contains

(

const SeqTreeObj *

sto

)

const [inline]

Returns true if 'sto' can be found in the objects branch of the sequence tree

Reimplemented from SeqTreeObj.

Definition at line 334 of file seqacqepi.h.

bool SeqAcqEPI::contains

(

objCategory

cat

)

const [inline]

Returns true if any object of category 'cat' can be found in the objects branch of the sequence tree

Reimplemented from SeqTreeObj.

Definition at line 335 of file seqacqepi.h.

void SeqAcqEPI::tree

(

SeqTreeCallbackAbstract *

display

)

const [inline]

Generates a graphical representation of the sequence tree using 'display'

Reimplemented from SeqTreeObj.

Definition at line 336 of file seqacqepi.h.

unsigned int SeqAcqEPI::event

(

eventContext &

context

)

const [inline, virtual]

Queries the sequence tree for events, returns the number of events executed

Reimplemented from SeqTreeObj.

Definition at line 337 of file seqacqepi.h.

STD_string SeqAcqEPI::get_properties

(

)

const [inline, virtual]

Returns a string describing the object

Reimplemented from SeqTreeObj.

Definition at line 338 of file seqacqepi.h.

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

• seqacqepi.h

---