contract Subroutine

  1. mortif.f90
  2. mortif
  3. contract

private elemental subroutine contract(i, b, z, c)

Contract integer of 64 bits into integer of 32 bits.

See On Spatial Orders and Location Codes, Stocco, LJ and Schrack, G, IEEE Transaction on Computers, vol 58, n 3, March 2009. The resulting integer(int8/int16/int32) has only b' significant bits obtained by the following contraction: ifbb/zx0/bb-1/zx0../b1/zx0/b0 => bb/bb-1/…/b1/b0; e.g. for(b=4,z=1):b3/0/b2/0/b1/0/b0 => b3/b2/b1/b0`.

Arguments

Type IntentOptional AttributesName
integer(kind=I8P), intent(in) :: i

Input integer.
integer(kind=I2P), intent(in) :: b

Number of significant bits of 'i' (2/4/8/16/32).
integer(kind=I1P), intent(in) :: z

Number of zero 'i' (1/2).
integer(kind=I4P), intent(out) :: c

Contracted integer.

Called By

proc~~contract~~CalledByGraph proc~contract contract proc~demorton2d demorton2D proc~demorton2d->proc~contract proc~demorton3d demorton3D proc~demorton3d->proc~contract proc~test_morton3d test_morton3D proc~test_morton3d->proc~demorton3d program~mortif_test_correctness mortif_test_correctness program~mortif_test_correctness->proc~test_morton3d
Help

Source Code

contract

Source Code

  elemental subroutine contract(i, b, z, c)
  !---------------------------------------------------------------------------------------------------------------------------------
  !< Contract integer of 64 bits into integer of 32 bits.
  !<
  !< See *On Spatial Orders and Location Codes*, Stocco, LJ and Schrack, G, IEEE Transaction on Computers, vol 58, n 3, March 2009.
  !< The resulting integer(int8/int16/int32) has only `b' significant bits obtained by the following contraction:
  !< if `bb/zx0/bb-1/zx0../b1/zx0/b0 => bb/bb-1/.../b1/b0`; e.g. for `(b=4,z=1)`: `b3/0/b2/0/b1/0/b0 => b3/b2/b1/b0`.
  !---------------------------------------------------------------------------------------------------------------------------------
  integer(I8P), intent(in)  :: i !< Input integer.
  integer(I2P), intent(in)  :: b !< Number of significant bits of 'i' (2/4/8/16/32).
  integer(I1P), intent(in)  :: z !< Number of zero 'i' (1/2).
  integer(I4P), intent(out) :: c !< Contracted integer.
  integer(I8P)              :: d !< Temporary dilated integer.
  integer(I1P)              :: m !< Counter.
  !---------------------------------------------------------------------------------------------------------------------------------

  !---------------------------------------------------------------------------------------------------------------------------------
  d = iand(i, mask(1,z))
  do m=1_I1P, int(log10(b*1._R4P)*log10_2_inv, I1P), 1_I1P !(1,5/4/3/2/1)
    d = iand(ieor(d, ishft(d, -shft(m,z))), mask(m+1,z))
  enddo
  c = int(d, I4P)
  !---------------------------------------------------------------------------------------------------------------------------------
  endsubroutine contract

All Procedures