#======================================================================

#                    M E R G E C T D + L A D C P . L A D C P T I M E S E R I E S 

#                    doc: Sun May 23 16:40:53 2010

#                    dlm: Sat Oct 30 22:23:33 2010

#                    (c) 2010 A.M. Thurnherr

#                    uE-Info: 11 60 NIL 0 0 72 0 2 4 NIL ofnI

#======================================================================

# HISTORY:

#	May 23, 2010: - created from [perl-tools/RDI_Utils.pl]

#	Oct 20, 2010: - disabled max_gap profile-restarting code

# NOTES:

#	- resulting DEPTH field based on integrated w without any sound speed correction

#	- single-ping ensembles assumed, i.e. no percent-good tests applied

#	- specified bin numbers are 1-relative

sub ref_lr_w($$$$)										# calc ref-layer vert vels

{

	my($dta,$ens,$rl_b0,$rl_b1) = @_;

	my($i,@n,@bn,@v,@vel,@bv,@w);

	for ($i=$rl_b0-1; $i<=$rl_b1-1; $i++) {

		if (defined($dta->{ENSEMBLE}[$ens]->{W}[$i])) {							# valid w

			$vel[2] += $dta->{ENSEMBLE}[$ens]->{W}[$i]; $n[2]++;

			$vel[3] += $dta->{ENSEMBLE}[$ens]->{ERRVEL}[$i], $n[3]++ if defined($dta->{ENSEMBLE}[$ens]->{ERRVEL}[$i]);

			push(@w,$dta->{ENSEMBLE}[$ens]->{W}[$i]); 							# for stderr test

		}

	}

	my($w) = $n[2] ? $vel[2]/$n[2] : undef;				# w uncertainty

	my($sumsq) = 0;

	for ($i=0; $i<=$#w; $i++) {

		$sumsq += ($w-$w[$i])**2;

	}

	my($stderr) = $n[2]>=2 ? sqrt($sumsq)/($n[2]-1) : undef;

#	The following stderr test introduces a huge gap near the bottom of

#	the profiles. Without it, they seem more reasonable.

#	next if ($stderr > 0.05);

	if (defined($w)) {									# valid w

		$dta->{ENSEMBLE}[$ens]->{REFLR_W} = $w;

		$dta->{ENSEMBLE}[$ens]->{REFLR_W_ERR} = $stderr;

	}

}

#======================================================================

# ($firstgood,$lastgood,$atbottom,$w_gap_time) =

#	calcLADCPts($dta,$lr_b0,$lr_b1,$min_corr,$max_e,$max_gap);

#======================================================================

sub calcLADCPts($$$)

{

	my($dta,$rl_b0,$rl_b1,$max_gap) = @_;

	my($firstgood,$lastgood,$atbottom,$w_gap_time,$maxz);

	for (my($z)=0,my($e)=0; $e<=$#{$dta->{ENSEMBLE}}; $e++) {

		ref_lr_w($dta,$e,$rl_b0,$rl_b1);

		if (defined($firstgood)) {

			$dta->{ENSEMBLE}[$e]->{ELAPSED_TIME} =			# time since start

				$dta->{ENSEMBLE}[$e]->{UNIX_TIME} -

				$dta->{ENSEMBLE}[$firstgood]->{UNIX_TIME};

		} else {

			if (defined($dta->{ENSEMBLE}[$e]->{REFLR_W})) {		# start of prof.

				$firstgood = $lastgood = $e;		    

				$dta->{ENSEMBLE}[$e]->{ELAPSED_TIME} = 0;

			}

			next;

		}

		#--------------------------------------------------

		# within profile: both $firstgood and $lastgood set

		#--------------------------------------------------

		if (!defined($dta->{ENSEMBLE}[$e]->{REFLR_W})) {			# gap

			$w_gap_time += $dta->{ENSEMBLE}[$e]->{UNIX_TIME} -

						   $dta->{ENSEMBLE}[$e-1]->{UNIX_TIME};

			next;

		}

		my($dt) = $dta->{ENSEMBLE}[$e]->{UNIX_TIME} -		# time step since

				  $dta->{ENSEMBLE}[$lastgood]->{UNIX_TIME}; # ... last good ens

#		if ($dt > $max_gap) {

#			printf(STDERR "\n\nWARNING: long gap (%ds). Profile restarted at ensemble #$dta->{ENSEMBLE}[$e]->{NUMBER}\n",$dt);

#			$firstgood = $lastgood = $e;

#			undef($atbottom); undef($maxz);

#			$z = 0;

#			$dta->{ENSEMBLE}[$e]->{ELAPSED_TIME} = 0;

#			$w_gap_time = 0;

#			next;

#		}

		#-----------------------------------

		# The current ensemble has a valid w

		#-----------------------------------

		$z += $dta->{ENSEMBLE}[$lastgood]->{REFLR_W} * $dt;			# integrate

		$atbottom = $e, $maxz = $z if ($z > $maxz); 

		$lastgood = $e;

	}

	return ($firstgood,$lastgood,$atbottom,$w_gap_time);

}

1;