ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c "bins"  sorts the data into files by bins.
c               It also creates header for ZOO files
c
c
c amue Jan. 23, 1997
c
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine bins(nav,name,nzmax,ndata,dt,ibinsize,zscale,mon)
	common /ini2/c30,s30,c,fact,fact1,xsc_lat,pi,d2r
c	
	real c30,s30,c,fact,fact1,pi,d2r
	double precision xsc_lat
	character file1*12,file2*12,label*4,path*20,adcp*49,nav*49,all1*93 
	character name*38,input*12,cal_name*16,all*89,name1*10,zname*10,btname*10
	character biname*10,trans*95,header1*60,header2*60
	character h_title(10)*14,h_units(10)*14,h_date*12
	character zoo_file*44,file3*8
	real h_val(10)
	real uu(13000),vv(13000)
	integer mon(12)
c
	tsca2 = 24.*60.*60.
	tsca3 = 60.*60.

	write(6,*)nav
	open (unit=11,file=nav)
c
	read(11,129)nfields,iy,im,iday,ih,iy1,im1,iday1,ih1,file3,ibin1
	write(6,129)nfields,iy,im,iday,ih,iy1,im1,iday1,ih1,file3,ibin1
129	format(9(i2,1x),a8,1x,i4)
	read(11,120) h_title(1),h_units(1),h_date
	write(6,120) h_title(1),h_units(1),h_date
120	format(a10,1x,a12,1x,a12)
	read(11,*)(h_title(j),h_units(j),h_val(j),j=2,nfields)
	write(6,*)(h_title(j),h_units(j),h_val(j),j=2,nfields)
	read(11,118)header1
	read(11,118)header2
118	format(a60)
	close (11)

c magnetic rotation by 12.5 degrees ccw
c
	arg = pi*12.5/180.
	tstart = ( (mon(im)+ iday)* tsca2+ ih*tsca3 )/tsca2
	tend   = ( (mon(im1)+iday1)*tsca2+ih1*tsca3 )/tsca2
	do 11 ibin=1,nzmax
		write(6,*)'processing zoo-file for bin #:',ibin
		open(unit=10,file='tem')
		open(unit=13,file=name)
		t_old = tstart
		ntrans = 0
	do 9 idata=1,ndata
		read(13,*)t,y,x,ib,u,v,temp,avg_int,avg_cor,avg_pg,shipbar,w,e
		if (t.ge.tstart .and. t.le.tend .and. ib.eq.ibin) then
			ddt = t-t_old
			if (ddt*24.*60. .le. dt+2.) then
				urot = ( u*cos(arg)+v*sin(arg))
				vrot = (-u*sin(arg)+v*cos(arg))
				ntrans = ntrans+1
				uu(ntrans) = urot
				vv(ntrans) = vrot
				write(10,117)t,vrot,urot,temp,avg_int,avg_cor,avg_pg,w,e
117				format(4f10.3,3f7.0,2f10.3)
116				format(4f10.3,' NaN NaN NaN NaN NaN')
			else
				ngap = ddt*60.*24./dt
				if (ngap.eq.1) then
					tt = t_old+dt/60./24
					write(10,117)tt,vrot,urot,temp,avg_int,avg_cor,avg_pg,w,e
					ntrans = ntrans+1
				else if (ngap.eq.2) then
					tt = t_old+dt/60./24
					write(10,117)tt,vrot,urot,temp,avg_int,avg_cor,avg_pg,w,e
					tt = t_old+2.*dt/60./24
					write(10,117)tt,vrot,urot,temp,avg_int,avg_cor,avg_pg,w,e
					ntrans = ntrans+2
				else if (ngap.le.13) then
					do 25 igap=1,ngap
						ntrans = ntrans+1
						tt = t_old+float(igap)*dt/24./60.
						write(10,116)tt,vv(ntrans-12),uu(ntrans-12),temp
25					continue
					write(666,*)t,ngap,' records tidal fill in bin',ibin
				else
					do 12 igap=1,ngap
						write(10,128)
						ntrans = ntrans+1
128						format('NaN NaN NaN NaN NaN NaN NaN NaN NaN')
12					continue
					write(666,*)t,ngap,'records missing in bin',ibin
					write(6,*)ngap,' records missing in bin',ibin
				end if
			end if
			t_old = t
		end if
9	continue
	close (10)
	close (13)
	open (unit=10,file='tem')
c
	open (unit=12,file='tem1')
	if(ibin.lt.10) write(12,125)file3,ibin
	if(ibin.ge.10) write(12,126)file3,ibin
c125	format('/d54/data/moor/bb96/process/gap/',a8,'.00',i1)
c126	format('/d54/data/moor/bb96/process/gap/',a8,'.0',i2)
125	format('/home/muenchow/9606/moor/bbmoor/',a8,'.00',i1)
126	format('/home/muenchow/9606/moor/bbmoor/',a8,'.0',i2)
	close (12)
	open (unit=12,file='tem1')
	read(12,127)zoo_file
127	format(a44)
	close (12)
c
	open(unit=12,file=zoo_file)
	h_title(4) = 'inst_height'
	h_units(4) = 'meters'
	depth =h_val(7)
	write(12,123)(h_title(j),j=1,nfields)
123	format(a13,a7,a12,a11,1x,2a4,a8)
	write(12,123)(h_units(j),j=1,nfields)
c
	zbin = 0.01*(float(ibin1)+float((ibin-1)*ibinsize)*zscale) 
c	if (xx.eq.960xbbc2) then
		zoff = 1.03
c	end if
c
c	write(12,119)h_date,ntrans,dt*60,depth-zbin,h_val(5),h_val(6),h_val(7)
	write(12,119)h_date,ntrans,dt*60,zbin+zoff,h_val(5),h_val(6),h_val(7)
119	format(1x,a12,1x,i5,f8.2,f7.2,2f10.4,f6.1)
c	write(12,*)header1
c	write(12,*)header2
	write(12,*)'time north east temp intensity correlation pg vertical error'
	write(12,*)'year_day cm_s cm_s deg_C db counts % cm_s cm_s'
	do 10 idata=1,ntrans
		read(10,124)all1
		write(12,124)all1
124		format(a80)
10	continue
	close (10)
	close (12)
11	continue
	return
	end
cccccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c
c
cccccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine sticks(n,uu,vv,tt)
	real uu(*),vv(*),tt(*)
	real xscale,yscale
	integer n
	data zero/0./,uscale/1./
	vscale = (600./6)/(100./2.)
c                  50    /   50
	r2d = 180./atan(1.)/4.
c
	open (unit=61,file='adcp-stick.plt')
c	open (unit=62,file='adcp-stick.dat')
	do 1 i=2,n
		speed = sqrt(uu(i)*uu(i)+vv(i)*vv(i))
		dir = atan2(uu(i),vv(i))*r2d
		v = -uu(i)*uscale
		u = vv(i)*vscale
		t0 = tt(i)
		write(61,101)t0,zero,speed,dir
		write(61,101)t0+u,v,speed,dir
		write(61,101)t0,zero,speed,dir
1	continue
c
101	format(4f10.1)
	return
	end
cccccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c "plt_vs" plots variables related to the ship's speed
c
c 05-07-1992 amue
c
ccccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine plt_vs(nens)
	common /names/label
	character label*2,name*8,name2*8,all*80
c
	open (unit=10,file='scratch')
	write(3,*)'plotxy ',name 
		write(10,101)label,label
101	format('pltvs.',a2,'vshp.',a2)
	close(10)
	open (unit=10,file='scratch')
		read(10,102)name,name2
		write(3,*)'plotxy ',name
	write(3,*)'plotxy ',name 
102	format(2a8)
	close(10)
c 
	open (unit=13,file=name2)
	open (unit=10,file='vship.dat')
		do 1 i=1,nens
			read(10,103)all
			write(13,103)all
1		continue
103	format(a80)
	close (13)
	close(10)
c
	open (unit=12,file=name)
	dt = nens/10
c speed BT
	write(12,104)name2,name2,name2,name2,name2,name2,label
104	format(	'file ',a9/'mode 20 1 3'/'read'/'xlim 6'/'ylim 1.5'/
     1		'xlab Ensemble'/'ylab Speed (cm/s)'/'save'/
c speed GPS
     1		'file ',a9/'mode 20 1 4'/'dash'/'read'/'plot'/'stack'/
c dir. BT
     1		'file ',a9/'mode 20 1 5'/'dash 0 0'/'read'/
     1			'ylab Direction (deg.)'/'save'/
c dir. GPS
     1		'file ',a9/'mode 20 1 6'/'dash'/'read'/'plot'/'stack'/
c BT-GPS
     1		'file ',a9/'mode 20 1 7'/'dash 0 0'/'read'/
     1				'ylab GPS-BT (cm/s)'/'plot'/'stack'/
c BT-GPS
     1		'file ',a9/'mode 20 1 8'/'read'/'ylab GPS-BT (deg.)'/
     1				'title ',a2/'plot'/'stop'/)
	return
	end
cccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c "plt_tilt" plots the tilt sensor output for each ensemble
c
c 05-07-1992 amue
c
ccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine plt_tilt(nens)
	common /names/label
	character label*2,name*8,name2*8,all*101
c
	open (unit=10,file='scratch')
		write(10,101)label,label
101	format('pltxy.',a2,'tilt.',a2)
	close(10)
	open (unit=10,file='scratch')
		read(10,102)name,name2
		write(3,*)'plotxy ',name
102	format(2a8)
	close(10)
c 
	open (unit=13,file=name2)
	open (unit=10,file='tilt.dat')
		do 1 i=1,nens
			read(10,103)all
			write(13,103)all
1		continue
103	format(a101)
	close (13)
	close(10)
c
	open (unit=12,file=name)
	dt = nens/10
c head
	write(12,104)name2,name2,name2,name2,label
104	format('file ',a9/'mode 20 1 3'/'read'/'xlim 6'/'ylim 1.5 0 360 90'/
     1		'xlab Ensmble'/'ylab Heading (deg.)'/'plot'/'stack'/
c pitch	
     1		'file ',a9/'mode 20 1 5'/'read'/'ylim 1.5 -20 20 5'/
     1			'ylab Pitch (deg.)'/'plot'/'stack'/
c roll
     1		'file ',a9/'mode 20 1 7'/'read'/'ylim 1.5 -20 20 5'/
     1			'ylab Roll (dg.)'/'plot'/'stack'/
c bte
     1		'file ',a9/'mode 20 1 10'/'read'/'ylim 1.5 -5 5 1'/
     1			'ylab bte (m/s)'/'title ',a2/'plot'/'stop')
	close (12)
	return
	end
cccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c "plt_vel" plots the velocity data output for each ensemble
c
c 12-21-1992 amue
c
ccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine plt_vel(nens,ivel)
	common /names/label
	character label*2,name*9,name2*9,all*62
c
	open (unit=10,file='scratch')
		write(10,101)label,label
101	format('pltvel.',a2,'datvel.',a2)
	close(10)
	open (unit=10,file='scratch')
		read(10,102)name,name2
		write(3,*)'plotxy ',name
102	format(2a9)
	close(10)
c 
	open (unit=13,file=name2)
	open (unit=10,file='velocity.dat')
		do 1 i=1,ivel
			read(10,103)iens,time,z,all
			if (z.eq.2.) then
				write(13,103)iens,time,z,all
			end if
1		continue
103	format(1x,i5,f15.2,f7.1,a62)
	close (13)
	close(10)
c
	open (unit=12,file=name)
	dt = nens/10
c
	write(12,104)name2,name2,name2,label
c vxe
104	format('file ',a9/'mode 20 1 4'/'read'/'xlim 6'/'ylim 2 -50 50'/
     1		'xlab Ensemble'/'ylab vxe (cm/s)'/'plot'/'stack'/
c vye 
     1		'file ',a9/'mode 20 1 5'/'read'/'ylab vye (cm/s)'/'plot'/'stack'/
c ve
     1		'file ',a9/'mode 20 1 7'/'read'/'ylab ve (cm/s)'/
     1			'title ',a2/'plot'/'stack'/)
	close (12)
	return
	end
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c "co_sys" for rthe co-ordinate transormation matrix elements
c
c 3/35/92 amue
c
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine co_sys(c,scale,line2,zsg,sig_up)
	real zsg(*),c,scale,sig_up
	integer line2(*)
c
c get scale for co-ordinate transformation
c
c transmit frequency (Hz)
	ft = line2(17)*1000.
c range switch setting: high (1) or low (2)
	if (line2(13).eq.0) then
		rss = 0.125
	else if (line2(13).eq.1) then
		rss = 0.25
c
c line2(13)==2 indicates files originates from BB-ADCP processing
c i.e., no scaling is necessary as it is done in BBLIST 
c (what about the speed of sound that enters here?)
c
	else if (line2(13).eq.2) then
		rss = 99.9
	else
		write(6,*)'invalid range switch setting',line2(13)
		write(6,*)(line2(i),i=1,17)
		stop
	end if
c co-ordinates: beam (1) or earth (2)
	if (line2(14).eq.0) then
		vcs = 1.
	else if (line2(14).eq.1) then
		vcs = 2.
	else
		write(6,*)'invalid velocity co-ordinate system'
		stop
	end if  
c
c scale to convert counts to cm/s
c
	scale = rss*vcs*c/1536.
	if (rss.gt.1) then
		write(6,*)
		write(6,*)'BB-ADCP processing, scale set to 0.1'
		write(4,*)'BB-ADCP processing, scale set to 0.1'
		write(6,*)
c		T = 9.
c		D = 20.
c		S = 31.
c		c = 1449.7+4.6*T-0.055*T*T+0.00029*T*T*T
c		c = c+(1.34-0.01*T)*(S-35)+0.016*D
	write(6,*)'speed of sound use',c
	write(4,*)'speed of sound use',c
		scale = 0.1*c/1500.
	end if
c
c get sign for co-ordinate transformation
c
	if (line2(15).eq.1 .and. line2(16).eq.0) then
		write(4,*)'downward, convex transducer'
		zsg(1) =  1.
		zsg(2) = -1.
		zsg(3) = -1.
		zsg(4) =  1.
		sig_up = 1.
	else if (line2(15).eq.1 .and. line2(16).eq.1) then
		write(4,*)'downward, concave transducer'
		zsg(1) = -1.
		zsg(2) =  1.
		zsg(3) =  1.
		zsg(4) = -1.
		sig_up = 1.
	else if (line2(15).eq.0 .and. line2(16).eq.0) then
		write(4,*)'upward, convex transducer'
		zsg(1) =  1.
		zsg(2) = -1.
		zsg(3) =  1.
		zsg(4) = -1.
		sig_up = -1.
	else if (line2(15).eq.0 .and. line2(16).eq.1) then
		write(4,*)'upward, concave transducer'
		zsg(1) = -1.
		zsg(2) =  1.
		zsg(3) = -1.
		zsg(4) =  1.
		sig_up = -1.
	end if
	write(4,*)'scale (co_sys): ',scale
	return
	end 
ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c
c
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine read_raw(iens,ncell,nz,izcut)
	common /raw/line1(6),line2(17),line3(5),line4(8),line5(13),line6(5),
     1			line(128,18),id(128),d1(128),d2(128),d3(128),d4(128),
     1			bt1,bt2,bt3,bt4,h1,h2,h3,h4,ncol
	integer bt1,bt2,bt3,bt4,h1,h2,h3,h4
	integer line1,line2,line3,line4,line5,line6,dummy(18)
	integer line,id,ncol,izcut,iens,ncell,nz
	real d1,d2,d3,d4
c date
		read(8,*)iens,(line1(j),j=2,6)
c		write(6,*)iens,(line1(j),j=2,6)
c set-up
		read(8,*)iens,(line2(j),j=2,17)
c health
		read(8,*)iens,(line3(j),j=2,5)
c tilt
		read(8,*)iens,(line4(j),j=2,8)
c b-track
c		read(8,*)iens,(line5(j),j=2,13)
		read(8,*)iens,bt1,bt2,bt3,bt4,h1,h2,h3,h4,(line5(j),j=10,13)
c CTD
		read(8,*)iens,(line6(j),j=2,5)
c Velocity Profile
		ncell = line2(6)-izcut
c		if (ncell.gt.nz) then
c			write(6,*)'# of depth cells read in header (iens)',ncell,iens
c			write(6,*)'increase dimension for nz (# of bins)'
c			stop
c		end if
c
c doppler shift of beam #1 to #4 in counts
c
		do 3 ib=1,min(ncell,nz)
			read(8,*)iens,ibin,(line(ib,j),j=3,ncol)
			d1(ibin) = line(ibin,3)
			d2(ibin) = line(ibin,4)
			d3(ibin) = line(ibin,5)
			d4(ibin) = line(ibin,6)
			id(ibin) = max(d1(ibin),d2(ibin),d3(ibin),d4(ibin))
3		continue
		if (ncell.gt.nz) then
			do 4 ib=nz+1,ncell
				read(8,*)iens,ibin,(dummy(j),j=3,ncol)
4			continue
			ncell = nz
		end if
	return
	end
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c bb-adcp
c
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine readbraw(iens,ncell,nz,izcut,tilt)
	common /raw/line1(6),line2(17),line3(5),line4(8),line5(13),line6(5),
     1			line(85,18),id(85),d1(85),d2(85),d3(85),d4(85),
     1			bt1,bt2,bt3,bt4,h1,h2,h3,h4,ncol
	integer bt1,bt2,bt3,bt4,h1,h2,h3,h4
	integer line1,line2,line3,line4,line5,line6
	integer line,id,ncol
	real d1,d2,d3,d4,tilt(8)
c date
		read(8,*)iens,(line1(j),j=2,6)
c		write(6,*)iens,(line1(j),j=2,6)
c set-up
		read(8,*)iens,(line2(j),j=2,17)
c	write(6,*)iens,(line2(j),j=2,17)
c		read(5,*)dummy
c health
		read(8,*)iens,(line3(j),j=2,5)
c		write(6,*)iens,(line3(j),j=2,5)
c tilt
		read(8,*)iens,(tilt(j),j=2,8)
c		write(6,*)iens,(tilt(j),j=2,8)
c b-track
c		read(8,*)iens,(line5(j),j=2,13)
		read(8,*)iens,bt1,bt2,bt3,bt4,h1,h2,h3,h4,(line5(j),j=10,13)
c		read(8,*)iens,bt1,bt2,bt3,bt4,h1,h2,h3,h4
c		write(6,*)iens,bt1,bt2,bt3,bt4,h1,h2,h3,h4,(line5(j),j=10,13)
c CTD
		read(8,*)iens,(line6(j),j=2,5)
c		write(6,*)iens,(line6(j),j=2,5)
c Velocity Profile
		ncell = line2(6)-izcut
		if (ncell.gt.nz) then
			write(6,*)'# of depth cells read in header (iens)',ncell,iens
			write(6,*)'increase dimension for nz (# of bins)'
			stop
		end if
c
c doppler shift of beam #1 to #4 in counts
c
		do 3 ib=1,ncell
			read(8,*)iens,ibin,(line(ibin,j),j=3,ncol)
			d1(ibin) = line(ibin,3)
			d2(ibin) = line(ibin,4)
			d3(ibin) = line(ibin,5)
			d4(ibin) = line(ibin,6)
			id(ibin) = max(d1(ibin),d2(ibin),d3(ibin),d4(ibin))
3		continue
	return
	end
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c os-adcp
c
cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine read_os(iens,ncell,nz)
	common /raw/line1(6),line2(17),line3(5),line4(8),line5(13),line6(5),
     1			line(85,18),id(85),d1(85),d2(85),d3(85),d4(85),
     1			bt1,bt2,bt3,bt4,h1,h2,h3,h4,ncol
	integer bt1,bt2,bt3,bt4,h1,h2,h3,h4
	integer line1,line2,line3,line4,line5,line6
	integer line,id,ncol
	real d1,d2,d3,d4,tilt(8)
c date
		read(91,*)iens,(line1(j),j=2,6)
c		write(6,*)iens,(line1(j),j=2,6)
c set-up
		read(92,*)iens,(line2(j),j=2,17)
c	write(6,*)iens,(line2(j),j=2,17)
c		read(5,*)dummy
c health
c		read(93,*)iens,(line3(j),j=2,5)
c		write(6,*)iens,(line3(j),j=2,5)
c tilt
		read(94,*)iens,(line4(j),j=2,8)
c		write(6,*)iens,(line4(j),j=2,8)
c b-track
c		read(8,*)iens,(line5(j),j=2,13)
		read(96,*)iens,bt1,bt2,bt3,bt4,h1,h2,h3,h4
		read(95,*)iens,(line5(j),j=10,13)
c		write(6,*)iens,bt1,bt2,bt3,bt4,h1,h2,h3,h4,(line5(j),j=10,13)
c CTD
c		read(8,*)iens,(line6(j),j=2,5)
c		write(6,*)iens,(line6(j),j=2,5)
c Velocity Profile
		ncell = line2(6)
		if (ncell.gt.nz) then
			write(6,*)'# of depth cells read in header (iens)',ncell,iens
			write(6,*)'increase dimension for nz (# of bins)'
			stop
		end if
c
c doppler shift of beam #1 to #4 in counts
c
		do 3 ib=1,ncell
			read(97,*)iens,ibin,(line(ibin,j),j=3,6)
			read(98,*)iens,ibin,(line(ibin,j),j=7,10)
			read(89,*)iens,ibin,(line(ibin,j),j=11,14)
			read(88,*)iens,ibin,(line(ibin,j),j=15,18)
c			read(8,*)iens,ibin,(line(ibin,j),j=3,ncol)
			d1(ibin) = line(ibin,3)
			d2(ibin) = line(ibin,4)
			d3(ibin) = line(ibin,5)
			d4(ibin) = line(ibin,6)
			id(ibin) = max(d1(ibin),d2(ibin),d3(ibin),d4(ibin))
3		continue
	return
	end
cccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c
c
ccccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine initial(ifile)
	common /ini0/navg,nensemble,ivel,i_old,ntot,ical,nbt,nxy,
     1	            cheadbar,sheadbar,cpbar,spbar,crbar,srbar
	common /ini1/xbar,ybar,btxbar,btybar,btzbar,hbar,tbar,hsdbar,xship,yship
	common /ini2/c30,s30,c,fact,fact1,xsc_lat,pi,d2r
	double precision xsc_lat
	integer navg,nensemble,ivel,i_old,ntot,ical,nbt,nxy
	real cheadbar,sheadbar,cpbar,spbar,crbar,srbar,
     1	     xbar,ybar,btxbar,btybar,btzbar,hbar,tbar,hsdbar,
     1       c30,s30,c,fact,fact1,pi,d2r,xship,yship
c
	pi = 4.*atan(1.)
	d2r = pi/180.
	if (ifile.eq.1) then
999		write(6,*)'Enter beam angle: 20 for 20 deg. or 30 for 30 deg'
c		read(5,*)angle
		angle = 30.
998		write(6,*)'Enter speed of sound to be used in (m/s)'
c		read(5,*)c
		c = 1500
		if (c.gt.1600 .or. c.lt.1400) then
			write(6,*)'Are you sure about c=',c,'m/s? 1-yes, 0-no'
			read(5,*)ic
			if (ic.eq.0) goto 998
		end if
c
		c30 = cos(angle*pi/180.)
		s30 = sin(angle*pi/180.)
	end if
c convert tilt
	fact = 360./65536.
c convert temperature
	fact1 = 50./4096.
c convert lat to cm 
	xsc_lat = 60.*1852.*100.
c
	navg = 0
	nensemble = 0
	ivel = 0
	i_old = 1
	ntot = 0
	ical = 0
	nbt = 0
	nxy = 0
	cheadbar = 0.
	sheadbar = 0.
	cpbar = 0.
	spbar = 0.
	crbar = 0.
	srbar = 0.
	xbar = 0.
	ybar = 0.
	xship = 0.
	yship = 0.
	btxbar = 0.
	btybar = 0.
	btzbar = 0.
	hbar = 0.
	tbar = 0.
	hsdbar = 0.
	return
	end
ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
c
c "nav_scr" screens the nav data according to an algorithmn
c           originally developed in "boot_strap.f"
c
c 6/21/93 amue
c
ccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc
	subroutine nav_scr(n,t,x,y,ipass)
	parameter (nn=99000)
	real t(*),x(*),y(*),xx(nn),yy(nn)
	integer ipass
	if (n.gt.nn) then
		write(6,*)'increase dimensions "nav_scr"'
		stop
	end if
c
	pi = 4.*atan(1.)
	dt = (t(n)-t(1))/float(n)
	write(6,101)t(1)/60.,t(n)/60.,dt
	write(4,101)t(1)/60.,t(n)/60.,dt
101	format(/'start and end time (min):         ',2f10.0/
     1		'avg. time between ensembles (sec) ',f10.3/)
	id1 = 10
	id2 = 20
c
c 10 m/s ship speed corresponds to d1_crit, d2_crit meters 
c
	d1_crit = 10.*dt*float(id1)
	d2_crit = 10.*dt*float(id2)
	write(6,*)
	write(6,*)'id1,id2,d1_crit,d2_crit',id1,id2,d1_crit,d2_crit
	ipass = 0
	ifail = 0
	xsc = 60.*1852.
	do 4 i=id2+1,n-id2
		arg = pi*y(i)/180.
		ysc = xsc*cos(arg)
		dx1m = abs(x(i)-x(i-id1))*xsc
		dx1p = abs(x(i)-x(i+id1))*xsc
c
		dx2m = abs(x(i)-x(i-id2))*xsc
		dx2p = abs(x(i)-x(i+id2))*xsc
c
		dy1m = abs(y(i)-y(i-id1))*ysc
		dy1p = abs(y(i)-y(i+id1))*ysc
c
		dy2m = abs(y(i)-y(i-id2))*ysc
		dy2p = abs(y(i)-y(i+id2))*ysc
c
		dx = max(dx1m,dx1p,dx2m,dx2p)
		dy = max(dy1m,dy1p,dy2m,dy2p)
c
		if (    (dx1p.lt.d1_crit .and. dx1m.lt.d1_crit) .and.
     1			(dy1p.lt.d1_crit .and. dy1m.lt.d1_crit) .and.
     1			(dx2p.lt.d2_crit .and. dx2m.lt.d2_crit) .and.
     1			(dy2p.lt.d2_crit .and. dy2m.lt.d2_crit)) then
			yy(i) = y(i)
			xx(i) = x(i)
			ipass = ipass+1
			iflag = 0
		else
			ddt = t(i-1)-t(i-id1)
			ddx = (xx(i-1)-xx(i-id1))/ddt
			ddy = (yy(i-1)-yy(i-id1))/ddt
			xx(i) = xx(i-id1)+ddx*id1*dt
			yy(i) = yy(i-id1)+ddy*id1*dt
			iflag = 999
			ifail = ifail+1
		end if
		write(99,105)i,t(i),xx(i)*xsc,yy(i)*ysc,dx,dy,iflag
4	continue
	ipfail = float(ifail)/float(n)*100.
	write(6,*)'n,ipass.ifail,% failing ',n,ipass,ifail,ipfail
	write(4,*)'n,ipass.ifail,% failing ',n,ipass,ifail,ipfail
	write(4,*)
	l = 0
	do 9 i=id2+1,n-id2
		x(i) = xx(i)
		y(i) = yy(i)
9	continue
	n = l
105	format(i6,f10.3,2f11.5,2f15.2,i5)
	return
	end