Diffusion Weighting. More...
#include <seqdiffweight.h>
Public Member Functions | |
| SeqDiffWeight (const STD_string &object_label, const fvector &bvals, float maxgradstrength, const SeqObjBase &midpart, direction chan, bool stejskalTanner=false, const STD_string &nucleus="") | |
| SeqDiffWeight (const STD_string &object_label, unsigned int ndir, const fvector &bvals, float maxgradstrength, const SeqObjBase &midpart, unsigned int baseline_rep=0, bool stejskalTanner=false, const STD_string &nucleus="") | |
| SeqDiffWeight (const STD_string &object_label="unnamedSeqDiffWeight") | |
| SeqDiffWeight (const SeqDiffWeight &sgdw) | |
| SeqDiffWeight & | operator= (const SeqDiffWeight &sgdw) |
| const SeqGradInterface & | get_grad1 () const |
| const SeqGradInterface & | get_grad2 () const |
| double | get_grad1_duration () const |
| double | get_grad2_duration () const |
| double | get_midpart_duration () const |
| const darray & | get_b_vectors () 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) |
| void | clear_container () |
Detailed Description
Diffusion Weighting.
A bipolar gradient pulse for diffusion weighting
The b-value and the properties of the gradient pulses are connected through the equation
b = gamma^2 * delta^2 ( Delta - delta/3 ) G^2
- b: b-value
- gamma: gyromagnetic ratio
- delta: gradient pulse duration
- Delta: gradient pulse separation, the duration of midpart (sequence part which is enclosed by the two gradient) is considered here
- G: gradient strength
The order in which the series of b-values is played out can be cyclically reordered by using the vector which is returned by the get_reorder_vector() function: At each iteration of this vector, the b-values are exchanged cyclically.
Definition at line 53 of file seqdiffweight.h.
Constructor & Destructor Documentation
| SeqDiffWeight::SeqDiffWeight | ( | const STD_string & | object_label, | |
| const fvector & | bvals, | |||
| float | maxgradstrength, | |||
| const SeqObjBase & | midpart, | |||
| direction | chan, | |||
| bool | stejskalTanner = false, |
|||
| const STD_string & | nucleus = "" | |||
| ) |
Constructs a bipolar gradient pulse labeled 'object_label' with the following properties:
- bvals: The b-values for diffusion weighting, a postive value means that the first gradient pulse will have positive polarity and the second gradient pulse a negative polarity. These polarities are swapped in case of a negative b-value.
- maxgradstrength: The maximum gradient strength to use for the maximum b-value
- midpart: The sequence part which will be enclosed by the two gradient pulses.
- chan: The gradient channel for the gradient pulses.
- stejskalTanner: If set to 'true', both gradients will have the same polarity
- nucleus: The nucleus for which the gradient pulses will be calculated
| SeqDiffWeight::SeqDiffWeight | ( | const STD_string & | object_label, | |
| unsigned int | ndir, | |||
| const fvector & | bvals, | |||
| float | maxgradstrength, | |||
| const SeqObjBase & | midpart, | |||
| unsigned int | baseline_rep = 0, |
|||
| bool | stejskalTanner = false, |
|||
| const STD_string & | nucleus = "" | |||
| ) |
Constructs a bipolar gradient pulse labeled 'object_label' with the following properties:
- ndir: Number of uniformly ditributed directions
- bvals: The b-values for diffusion weighting, a postive value means that the first gradient pulse will have positive polarity and the second gradient pulse a negative polarity. These polarities are swapped in case of a negative b-value.
- maxgradstrength: The maximum gradient strength to use for the maximum b-value
- midpart: The sequence part which will be enclosed by the two gradient pulses.
- baseline_rep: Repetition rate of the baseline (b=0) scan. Not repeated if zero.
- stejskalTanner: If set to 'true', both gradients will have the same polarity
- nucleus: The nucleus for which the gradient pulses will be calculated
| SeqDiffWeight::SeqDiffWeight | ( | const STD_string & | object_label = "unnamedSeqDiffWeight" |
) |
Default constructor
| SeqDiffWeight::SeqDiffWeight | ( | const SeqDiffWeight & | sgdw | ) | [inline] |
Copy constructor
Definition at line 96 of file seqdiffweight.h.
Member Function Documentation
| void SeqDiffWeight::clear_container | ( | ) | [inline, virtual] |
Overload this function in case the class is a container object, i.e. it contains other sequence objects. The function should clear all references to other sequence objects, i.e. to thos it contains.
Reimplemented from SeqClass.
Definition at line 145 of file seqdiffweight.h.
| const darray& SeqDiffWeight::get_b_vectors | ( | ) | const [inline] |
Returns the b-vectors used in subsequent order.
Definition at line 131 of file seqdiffweight.h.
| const SeqGradInterface& SeqDiffWeight::get_grad1 | ( | ) | const [inline] |
Returns the first gradient lobe
Definition at line 106 of file seqdiffweight.h.
| double SeqDiffWeight::get_grad1_duration | ( | ) | const [inline] |
Returns the duration of the first gradient lobe
Definition at line 116 of file seqdiffweight.h.
| const SeqGradInterface& SeqDiffWeight::get_grad2 | ( | ) | const [inline] |
Returns the second gradient lobe
Definition at line 111 of file seqdiffweight.h.
| double SeqDiffWeight::get_grad2_duration | ( | ) | const [inline] |
Returns the duration of the second gradient lobe
Definition at line 121 of file seqdiffweight.h.
| double SeqDiffWeight::get_gradduration | ( | ) | const [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.
| fvector SeqDiffWeight::get_gradintegral | ( | ) | const [virtual] |
Returns the integral vector of the gradient course
Implements SeqGradInterface.
| double SeqDiffWeight::get_midpart_duration | ( | ) | const [inline] |
Returns the duration of the part in the middle between the two gradient lobes
Definition at line 126 of file seqdiffweight.h.
| float SeqDiffWeight::get_strength | ( | ) | const [virtual] |
Returns the strength of the gradient object
Implements SeqGradInterface.
| SeqGradInterface& SeqDiffWeight::invert_strength | ( | ) | [virtual] |
Changes the polarity of the gradient, i.e. inverts the sign of the gradient strength
Implements SeqGradInterface.
| SeqDiffWeight& SeqDiffWeight::operator= | ( | const SeqDiffWeight & | sgdw | ) |
Assignment operator
| SeqGradInterface& SeqDiffWeight::set_gradrotmatrix | ( | const RotMatrix & | matrix | ) | [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.
| SeqGradInterface& SeqDiffWeight::set_strength | ( | float | gradstrength | ) | [virtual] |
Changes the strength of the gradient object
Implements SeqGradInterface.
The documentation for this class was generated from the following file:
