module kinds_modTypes:
private type hilbert_tableVariables:
type (hilbert_table), private, parameter, dimension (0:3) :: tab = (/ hilbert_table ((/ 2, 1, -2 /), (/ 1, 0, 0, 2 /), (/ 0, 2, 3, 1 /), (/ 0, 3, 1, 2 /)), hilbert_table ((/ 1, 2, -1 /), (/ 0, 1, 1, 3 /), (/ 0, 1, 3, 2 /), (/ 0, 1, 3, 2 /)), hilbert_table ((/ -1, -2, 1 /), (/ 3, 2, 2, 0 /), (/ 3, 2, 0, 1 /), (/ 2, 3, 1, 0 /)), hilbert_table ((/ -2, -1, 2 /), (/ 2, 3, 3, 1 /), (/ 3, 1, 0, 2 /), (/ 2, 1, 3, 0 /)) /)Subroutines and functions:
public subroutine hilbert2d_c2i (lev, p, idx) public subroutine hilbert2d_i2c (lev, idx, p)
Routines accept position and hilbert-index starting at 1.
Author: Matthias Lieber
private type hilbert_table integer (kind=i_k), dimension (0:2) :: mv integer (kind=i_k), dimension (0:3) :: next integer (kind=i_k), dimension (0:3) :: num2ref integer (kind=i_k), dimension (0:3) :: ref2num end type hilbert_tableComponents:
mv | spatial moves of the curve |
next | next states when refinining (quadrant is sequence number) |
num2ref | sequence number on curve primitve to reference (spatial) quadrant |
ref2num | reference (spatial) quadrant to sequence number on curve primitve |
Values of the mv item are:
public subroutine hilbert2d_c2i (lev, p, idx) integer (kind=i_k), intent(in) :: lev integer (kind=i_k), intent(in), dimension (2) :: p integer (kind=i_k), intent(out) :: idx end subroutine hilbert2d_c2iParameters:
lev | level of the hilbert curve (1=2x2, 2=4x4, 3=8x8, etc) |
p | 2D coordinates [1 ... 2^lev] |
idx | index on the 2D hilbert curve [1 ... (2^lev)^2] |
Has logarithmic complexity: number of loop iterations = lev. Due to performance reasons, no checking of arguments is performend!
public subroutine hilbert2d_i2c (lev, idx, p) integer (kind=i_k), intent(in) :: lev integer (kind=i_k), intent(in) :: idx integer (kind=i_k), intent(out), dimension (2) :: p end subroutine hilbert2d_i2cParameters:
lev | level of the hilbert curve (1=2x2, 2=4x4, 3=8x8, etc) |
idx | index on the 2D hilbert curve [1 ... (2^lev)^2 ] |
p | 2D coordinates [1 ... 2^lev] |
Has logarithmic complexity: number of loop iterations = lev. Due to performance reasons, no checking of arguments is performend!