PVDPV Subroutine

  1. astro_module.f90
  2. astro_module
  3. PVDPV

public subroutine PVDPV(a, b, adb)

Inner (=scalar=dot) product of two pv-vectors.

Status: vector/matrix support routine.

Note

If the position and velocity components of the two pv-vectors are ( Ap, Av ) and ( Bp, Bv ), the result, A . B, is the pair of numbers ( Ap . Bp , Ap . Bv + Av . Bp ). The two numbers are the dot-product of the two p-vectors and its derivative.

History

  • IAU SOFA revision: 2006 November 13

Arguments

TypeIntentOptionalAttributesName
real(kind=wp), intent(in), dimension(3,2):: a

first pv-vector
real(kind=wp), intent(in), dimension(3,2):: b

second pv-vector
real(kind=wp), intent(out), dimension(2):: adb

A . B (see note)

Calls

proc~~pvdpv~~CallsGraph proc~pvdpv PVDPV proc~pdp PDP proc~pvdpv->proc~pdp

Contents

Source Code

PVDPV

Source Code

    subroutine PVDPV ( a, b, adb )

    implicit none

    real(wp),dimension(3,2),intent(in) :: a !! first pv-vector
    real(wp),dimension(3,2),intent(in) :: b !! second pv-vector
    real(wp),dimension(2),intent(out) :: adb !! A . B (see note)

    real(wp) :: adbd, addb

    !  A . B = constant part of result.
    call PDP ( a(1,1), b(1,1), adb(1) )

    !  A . Bdot
    call PDP ( a(1,1), b(1,2), adbd )

    !  Adot . B
    call PDP ( a(1,2), b(1,1), addb )

    !  Velocity part of result.
    adb(2) = adbd + addb

    end subroutine PVDPV