line_gyro_surface_intersect Subroutine

  1. fidasim.f90
  2. libfida
  3. line_gyro_surface_intersect

public subroutine line_gyro_surface_intersect(r0, v0, gs, t)

Calculates the times of intersection of a line and a gyro-surface

Arguments

Type IntentOptional AttributesName
real(kind=Float64), intent(in), dimension(3):: r0

Point on line
real(kind=Float64), intent(in), dimension(3):: v0

Direction of line
type(GyroSurface), intent(in) :: gs

Gyro-surface
real(kind=Float64), intent(out), dimension(2):: t

"time" to intersect

Called by

proc~~line_gyro_surface_intersect~~CalledByGraph proc~line_gyro_surface_intersect line_gyro_surface_intersect proc~gyro_range gyro_range proc~gyro_range->proc~line_gyro_surface_intersect proc~npa_gyro_range npa_gyro_range proc~npa_gyro_range->proc~gyro_range proc~npa_f npa_f proc~npa_f->proc~npa_gyro_range proc~npa_mc npa_mc proc~npa_mc->proc~npa_gyro_range program~fidasim fidasim program~fidasim->proc~npa_f program~fidasim->proc~npa_mc

Contents

Source Code

line_gyro_surface_intersect

Source Code

subroutine line_gyro_surface_intersect(r0, v0, gs, t)
    !+ Calculates the times of intersection of a line and a gyro-surface
    real(Float64), dimension(3), intent(in)  :: r0
        !+ Point on line
    real(Float64), dimension(3), intent(in)  :: v0
        !+ Direction of line
    type(GyroSurface), intent(in)            :: gs
        !+ Gyro-surface
    real(Float64), dimension(2), intent(out) :: t
        !+ "time" to intersect

    real(Float64), dimension(3) :: rr
    real(Float64) :: a, b, c, d, tp, tm

    rr = r0 - gs%center
    a = dot_product(v0, matmul(gs%A,v0))
    b = dot_product(rr, matmul(gs%A,v0)) + dot_product(v0,matmul(gs%A,rr))
    c = dot_product(rr, matmul(gs%A,rr)) - 1.0

    d = b**2 - 4*a*c
    if(d.lt.0.0) then
        t = 0.0
        return
    endif

    t(1) = (-b - sqrt(d))/(2*a)
    t(2) = (-b + sqrt(d))/(2*a)
    
end subroutine line_gyro_surface_intersect