WSJT-X/azdist.f

109 lines
3.0 KiB
FortranFixed
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subroutine azdist(MyGrid,HisGrid,utch,nAz,nEl,nDmiles,nDkm,
+ nHotAz,nHotABetter)
character*6 MyGrid,HisGrid,mygrid0,hisgrid0
real*8 utch,utch0
logical HotABetter,IamEast
real eltab(22),daztab(22)
data eltab/18.,15.,13.,11.,9.,8.,7.,6.,5.3,4.7,4.,3.3,2.7,
+ 2.,1.5,1.,0.8,0.6,0.4,0.2,0.0,0.0/
data daztab/21.,18.,16.,15.,14.,13.,12.,11.,10.7,10.3,10.,
+ 10.,10.,10.,10.,10.,10.,9.,9.,9.,8.,8./
data mygrid0/" "/,hisgrid0/" "/,utch0/-999.d0/
save
if(MyGrid.eq.HisGrid) then
naz=0
nel=0
ndmiles=0
ndkm=0
nhotaz=0
nhotabetter=1
go to 999
endif
if(mygrid.eq.mygrid0 .and. hisgrid.eq.hisgrid0 .and.
+ abs(utch-utch0).lt.0.1666667d0) go to 900
utch0=utch
mygrid0=mygrid
hisgrid0=hisgrid
utchours=utch
if(MyGrid(5:5).eq.' ') MyGrid(5:5)='m'
if(MyGrid(6:6).eq.' ') MyGrid(6:6)='m'
if(HisGrid(5:5).eq.' ') HisGrid(5:5)='m'
if(HisGrid(6:6).eq.' ') HisGrid(6:6)='m'
if(MyGrid.eq.HisGrid) then
Az=0.
Dmiles=0.
Dkm=0.0
El=0.
HotA=0.
HotB=0.
HotABetter=.true.
go to 900
endif
call grid2deg(MyGrid,dlong1,dlat1)
call grid2deg(HisGrid,dlong2,dlat2)
call geodist(dlat1,dlong1,dlat2,dlong2,Az,Baz,Dkm)
ndkm=Dkm/100
j=ndkm-4
if(j.lt.1) j=1
if(j.gt.21)j=21
if(Dkm.lt.500.0) then
El=18.0
else
u=(Dkm-100.0*ndkm)/100.0
El=(1.0-u)*eltab(j) + u*eltab(j+1)
endif
daz=daztab(j) + u * (daztab(j+1)-daztab(j))
Dmiles=Dkm/1.609344
tmid=mod(UTChours-0.5*(dlong1+dlong2)/15.0+48.0,24.0)
IamEast=.false.
if(dlong1.lt.dlong2) IamEast=.true.
if(dlong1.eq.dlong2 .and. dlat1.gt.dlat2) IamEast=.false.
azEast=baz
if(IamEast) azEast=az
if((azEast.ge.45.0 .and. azEast.lt.135.0) .or.
+ (azEast.ge.225.0 .and. azEast.lt.315.0)) then
C The path will be taken as "east-west".
HotABetter=.true.
if(abs(tmid-6.0).lt.6.0) HotABetter=.false.
if((dlat1+dlat2)/2.0 .lt. 0.0) HotABetter=.not.HotABetter
else
C The path will be taken as "north-south".
HotABetter=.false.
if(abs(tmid-12.0).lt.6.0) HotABetter=.true.
endif
if(IamEast) then
HotA = Az - daz
HotB = Az + daz
else
HotA = Az + daz
HotB = Az - daz
endif
if(HotA.lt.0.0) HotA=HotA+360.0
if(HotA.gt.360.0) HotA=HotA-360.0
if(HotB.lt.0.0) HotB=HotB+360.0
if(HotB.gt.360.0) HotB=HotB-360.0
900 continue
naz=nint(Az)
nel=nint(el)
nDmiles=nint(Dmiles)
nDkm=nint(Dkm)
nHotAz=nint(HotB)
nHotABetter=0
if(HotABetter) then
nHotAz=nint(HotA)
nHotABetter=1
endif
999 return
end