congen_bstree Module Reference

Determinant binary search tree. More...

Data Types
type	det_tree
	Determinant binary search tree. More...

Functions/Subroutines
subroutine	init_det_tree (this, ndo, nelt)
	Initialize determinant tree. More...
subroutine	final_det_tree (this)
	Finalize determinant tree. More...
integer function	locate_in_det_tree (this, det)
	Find a specific determinant in the storage. More...
subroutine	write_determinant (this, lu, id)
	Write determinat. More...
integer function	compare_determinats (this, i, j, data)
	Lexicographically compare two determinats. More...

Detailed Description

Authors

J Benda

Date

2018 - 2019

This module contains a special data structure, det_tree, used (e.g.) by CONGEN to carry out quick look-ups in the storage of determinants. It is based on the type "bstree" from libAMOR.

Function/Subroutine Documentation

compare_determinats()

integer function congen_bstree::compare_determinats	(	class(det_tree), intent(in)	this,
		integer, intent(in)	i,
		integer, intent(in)	j,
		type(c_ptr), intent(in), optional	data
	)

Authors

J Benda

Date

2018 - 2019

Binary tree needs a notion of order of its elements to be able to work with the data so efficiently. In case of arrays of numbers, the typical order is the "lexicographical" order. The array A is less than B if for the first position I for which A(I) /= B(I) holds that A(I) < B(I).

If any of the given indices is negative, the reference determinant stored within the predicate type is used instead.

Parameters

this	Determinant tree object to use
i	Index of the first determinant
j	Index of the second determinant
data	Additional payload required by base class interface. Not used in congen.

Returns

-1 if the first determinant is lexicographically less, 0 if they are equal, +1 if the first is greater.

Definition at line 172 of file congen_bstree.f90.

final_det_tree()

subroutine congen_bstree::final_det_tree

(

type(det_tree), intent(inout)

this

)

Authors

J Benda

Date

2019

Releases all allocated memory.

Parameters

this	Tree object to finalize

Definition at line 90 of file congen_bstree.f90.

Referenced by congen_bstree::det_tree::final_det_tree().

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init_det_tree()

subroutine congen_bstree::init_det_tree	(	class(det_tree), intent(inout)	this,
		integer, dimension(:), intent(in), pointer	ndo,
		integer, intent(in)	nelt
	)

Authors

J Benda

Date

2019

Stores pointer to the determinant storage, so that it can be used when comparing determinant indices in the binary search tree subroutines.

Parameters

this	Tree object to initialize
ndo	Determinant storage
nelt	Size of a determinant

Definition at line 68 of file congen_bstree.f90.

locate_in_det_tree()

integer function congen_bstree::locate_in_det_tree	(	class(det_tree), intent(inout)	this,
		integer, dimension(this % nelt), intent(in)	det
	)

Authors

J Benda

Date

2019

Return index in the determinant storage, where the given determinant is located. Return -1 when there is no such determinant.

Parameters

this	Tree object to search
det	Determinant to find (length nelt)

Definition at line 111 of file congen_bstree.f90.

write_determinant()

subroutine congen_bstree::write_determinant	(	class(det_tree), intent(in)	this,
		integer, intent(in)	lu,
		integer, intent(in)	id
	)

Authors

J Benda

Date

2019

Used in debuggind output of the whole tree.

Parameters

this	Binary search tree
lu	Unit for writing
id	Tree node id

Definition at line 133 of file congen_bstree.f90.