gsGridIterator< Z, mode, d, true > Class Template Reference

Detailed Description

template<class Z, int mode, short_t d>
class gismo::gsGridIterator< Z, mode, d, true >

Iterator over the Cartesian product of integer points in a tensor-product grid.

The iteration is done in lexicographic order.

• mode = 0 : iteration over [a, b) or [a, b] gsGridIterator<T,CUBE> grid(a,b);
• mode = 1 : iteration over the boundry points of [a, b) or [a, b] gsGridIterator<T,BDR> grid(a,b);
• mode = 2 : iteration over the vertices of [a, b) or [a, b] gsGridIterator<T,VERTEX> grid(a,b);

The open or closed case is determined by a constructor flag. A third argument, eg. gsGridIterator<T,CUBE,d> grid(a,b); specifies fixed size dimension d

Note

Iteration over the boundary including offsets is possible using the free functions in gsUtils/gsCombinatorics.h

Template Parameters

Z	type of the integer coordinates of the index vector
d	statically known dimension, or dynamic dimension if d = -1 (default value)
mode	0: all integer points in [a,b], 1: all points in [a,b), 2: vertices of cube [a,b]

Collaboration diagram for gsGridIterator< Z, mode, d, true >:

Public Member Functions
	gsGridIterator ()
	Empty constructor.
	gsGridIterator (point const &a, point const &b, bool open=true)
	Constructor using lower and upper limits. More...
	gsGridIterator (point const &b, bool open=true)
	Constructor using upper limit. The iteration starts from zero. More...
	gsGridIterator (gsMatrix< Z, d, 2 > const &ab, bool open=true)
	Constructor using lower and upper limits. More...
bool	isBoundary () const
	Returns true if the current point lies on a boundary.
bool	isCeil (int i) const
	Returns true if the i-th coordinate has maximal value.
bool	isFloor (int i) const
	Returns true if the i-th coordinate has minimal value.
const point &	lower () const
	Returns the first point in the iteration.
index_t	numPoints () const
	Returns the total number of points that are iterated.
point	numPointsCwise () const
	Returns the total number of points per coordinate which are iterated.
void	reset (point const &a, point const &b, bool open=true)
	Resets the iterator using new lower and upper limits. More...
void	reset ()
	Resets the iterator, so that a new iteration over the points may start.
point	strides () const
	Utility function which returns the vector of strides. More...
const point &	upper () const
	Returns the last point in the iteration.

Private Attributes
point	m_cur
	Current point pointed at by the iterator.
point	m_upp
	Iteration lower and upper limits.
bool	m_valid
	Indicates the state of the iterator.

Constructor & Destructor Documentation

gsGridIterator ( point const &  a, point const &  b, bool  open = true  )

inline

Constructor using lower and upper limits.

Parameters

a	lower limit (vertex of a cube)
b	upper limit (vertex of a cube)
open	if true, the iteration is performed for the points in $[a_i,b_i)$

gsGridIterator ( point const &  b, bool  open = true  )

inlineexplicit

Constructor using upper limit. The iteration starts from zero.

Parameters

b	upper limit (vertex of a cube)
open	if true, the iteration is performed for the points in $[0,b_i)$

gsGridIterator ( gsMatrix< Z, d, 2 > const &  ab, bool  open = true  )

inlineexplicit

Constructor using lower and upper limits.

Parameters

ab	Matrix with two columns, corresponding to lower and upper limits
open	if true, the iteration is performed for the points in $[a_i,b_i)$

Member Function Documentation

void reset ( point const &  a, point const &  b, bool  open = true  )

inline

Resets the iterator using new lower and upper limits.

Parameters

a	lower limit (vertex of a cube)
b	upper limit (vertex of a cube)
open	if true, the iteration is performed for the points in $[a_i,b_i)$

point strides ( ) const

inline

Utility function which returns the vector of strides.

Returns

An integer vector (stride vector). the entry \(s_i\) implies that the current \(i\)-th coordinate of the iterated point will appear again after \(s_i\) increments. Moreover, the dot product of (*this - this->lower()) with the stride vector results in the "flat index", i.e. the cardinal index of the point in the iteration sequence.

If the iteration starts from the point zero (this->lower()==zero), then the stride vector has the property that that when we add it to *this we obtain the next point in the iteration sequence. In this case the flat index is obtained by taking the dot product with *this.