#======================================================================
# T I M E _ L A G . P L
# doc: Fri Dec 17 21:59:07 2010
# dlm: Thu Apr 16 12:13:25 2015
# (c) 2010 A.M. Thurnherr
# uE-Info: 276 41 NIL 0 0 72 2 2 4 NIL ofnI
#======================================================================
# HISTORY:
# Dec 17, 2010: - created
# Dec 18, 2010: - adapted for multi-pass lagging
# Dec 20: 2010: - added code to adjust start and end of profile ens
# based on extent of CTD profile and guestimated time
# ofset
# Jun 26, 2010: - added heuristic to chose between weighted-mean and
# unambiguously best offsets
# - turned -3 criterion into warning when 3 lags are consecutive
# Jul 4, 2011: - increased MAX_ALLOWED_THREE_LAG_SPREAD from 2 to 3
# Jul 7, 2011: - removed window-mean w before time lagging to allow lagging
# of casts with large w
# Aug 4, 2011: - made code use weighted average unless best lag accounts for
# more than 2/3 of lags (instead of 50%)
# Sep 23, 2011: - added mad info to best lag guesses
# - removed window-doubling heuristics
# Oct 12, 2011: - moved defaults to [defaults.pl]
# - BUG: code did not work correctly when there were less than 3
# valid offsets
# - BUG: code did not work correctly unless all windows
# returned valid offsets
# Oct 13, 2011: - added $TL_out and $TL_hist_out
# - restricted 2nd-pass to time lags +-1.5s
# - tightened allowed spread for weighted-average calc
# - BUG: $le in &bestLag() could be > $lastGoodEns
# - disabled weighted-average offset calculation
# Oct 14, 2011: - improved handling of %PARAMs
# - BUG: last ens of window estimation was off, probably accounting
# for Oct 13 BUG (fix disabled)
# - renamed _out to out_
# Oct 17, 2011: - BUG: closed STDOUT caused problems with tee in plotting scripts
# Oct 19, 2011: - BUG: windowing did not work correctly for short casts
# - BUG: search restarting did not work correctly
# - modified edge-of-window heuristics
# - added step to remove all lags with mad > median(mads)
# Oct 20, 2011: - losened too-restrictive last step
# Oct 21, 2011: - BUG: forgot to update $n_valid_windows while removing outlier lags
# Oct 15, 2012: - added $cast_type to &calc_lag()
# - removed support for TLhist
# Oct 16, 2012: - renamed field elapsed to elapsed.LADCP for clarity
# - made failure "soft"
# Mar 23, 2012: - adapted to piece-wise time lagging
# Apr 22, 2013: - replaced $max_allowed_w by $opt_m, $TL_required_top_three_fraction by $opt_3
# May 14, 2013: - opt_m => w_max_lim
# Mar 3, 2014: - BUG: var-name typo
# May 23, 2014: - BUG: $s range check required in mad_w()
# Apr 16, 2015: - turned output specifies into lists (re-design of
# plotting sub-system)
# - BUG: executable flag was not set on file output
# - disabled active output when ANTS are not available
# - croak -> error
# DIFFICULT STATIONS:
# NBP0901#131 this requires the search-radius doubling heuristic
# TODO:
# - better seabed code (from LADCPproc)
my($TINY) = 1e-6;
sub mad_w($$$) # mean absolute deviation
{
my($fe,$le,$so) = @_; # first/last LADCP ens, CTD scan offset
my($sad) = my($n) = 0;
my($LADCP_mean_w,$CTD_mean_w,$nsamp) = (0,0,0);
for (my($e)=$fe; $e<=$le; $e++) { # first, calculate mean w in window
my($s) = int(($LADCP{ENSEMBLE}[$e]->{ELAPSED} + $CTD{TIME_LAG} - $CTD{ELAPSED}[0]) / $CTD{DT} + 0.5);
next unless ($s>=0 && $s<=$#{$CTD{ELAPSED}});
die("assertion failed\n" .
"\ttest: abs($LADCP{ENSEMBLE}[$e]->{ELAPSED} + $CTD{TIME_LAG} - $CTD{ELAPSED}[$s]) <= $CTD{DT}/2\n" .
"\te = $e, s = $s, ensemble = $LADCP{ENSEMBLE}[$e]->{NUMBER}"
) unless (abs($LADCP{ENSEMBLE}[$e]->{ELAPSED} + $CTD{TIME_LAG} - $CTD{ELAPSED}[$s]) <= $CTD{DT}/2+$TINY);
next unless numberp($LADCP{ENSEMBLE}[$e]->{REFLR_W});
my($dw) = $LADCP{ENSEMBLE}[$e]->{REFLR_W}-$LADCP_mean_w - ($CTD{W}[$s+$so]-$CTD_mean_w);
next unless (abs($dw) <= $w_max_lim);
$LADCP_mean_w += $LADCP{ENSEMBLE}[$e]->{REFLR_W};
$CTD_mean_w += $CTD{W}[$s+$so];
$nsamp++;
}
return 9e99 unless ($nsamp);
$LADCP_mean_w /= $nsamp;
$CTD_mean_w /= $nsamp;
for (my($e)=$fe; $e<=$le; $e++) { # now, calculate mad
my($s) = int(($LADCP{ENSEMBLE}[$e]->{ELAPSED} + $CTD{TIME_LAG} - $CTD{ELAPSED}[0]) / $CTD{DT} + 0.5);
my($dw) = $LADCP{ENSEMBLE}[$e]->{REFLR_W}-$LADCP_mean_w - ($CTD{W}[$s+$so]-$CTD_mean_w);
next unless numberp($LADCP{ENSEMBLE}[$e]->{REFLR_W});
next unless (abs($dw) <= $w_max_lim);
$sad += abs($dw);
$n++;
}
return ($n>0) ? $sad/$n : 9e99; # n == 0, e.g. in bottom gap
}
sub bestLag($$$$) # find best lag in window
{
my($fe,$le,$ww,$soi) = @_; # first/last LADCP ens, window width, scan-offset increment
die("assertion failed\n\tfe = $fe, le = $le, firstGoodEns = $firstGoodEns, lastGoodEns = $lastGoodEns")
unless ($fe>=$firstGoodEns && $le<=$lastGoodEns);
my($bestso) = 0; # error at first-guess offset
my($bestmad) = mad_w($fe,$le,0);
for (my($dso) = 1; $dso <= int($ww/2/$CTD{DT} + 0.5); $dso+=$soi) {
my($mad) = mad_w($fe,$le,-$dso);
$bestmad=$mad,$bestso=-$dso if ($mad < $bestmad);
$mad = mad_w($fe,$le,$dso);
$bestmad=$mad,$bestso=$dso if ($mad < $bestmad);
}
return ($bestso,$bestmad);
}
#----------------------------------------------------------------------
# carry out lag correlations and keep tally of the results
#----------------------------------------------------------------------
{ # STATIC SCOPE
my(@elapsed_buf,@so_buf,@mad_buf,@bmo_buf,@te_buf,$elapsed_min_buf);
sub calc_lag($$$$$)
{
my($n_windows,$w_size,$scan_increment,$first_ens,$last_ens) = @_;
my($search_radius) = $scan_increment==1 ? 3 : $w_size;
my($ctmsg);
if ($first_ens==$firstGoodEns && $last_ens==$lastGoodEns) { $ctmsg = "full-cast"; }
else { $ctmsg = "partial-cast"; }
RETRY:
my($failed) = undef;
progress("Calculating $n_windows $ctmsg time lags from ${w_size}s-long windows at %dHz resolution...\n",
int(1/$scan_increment/$CTD{DT}+0.5));
my($approx_CTD_profile_start_ens) =
$firstGoodEns + int(($CTD{ELAPSED}[0] - $CTD{TIME_LAG}) / $LADCP{MEAN_DT});
my($approx_CTD_profile_end_ens) =
$firstGoodEns + int(($CTD{ELAPSED}[$#{$CTD{ELAPSED}}] + $CTD{ELAPSED}[0] - $CTD{TIME_LAG}) / $LADCP{MEAN_DT});
my($approx_joint_profile_start_ens) = max($firstGoodEns,$approx_CTD_profile_start_ens) + 10;
my($approx_joint_profile_end_ens) = min($lastGoodEns,$approx_CTD_profile_end_ens) - 10;
debugmsg("profile start: $firstGoodEns -> $approx_joint_profile_start_ens\n");
debugmsg("profile end : $lastGoodEns -> $approx_joint_profile_end_ens\n");
my($window_ens) = int($w_size/$LADCP{MEAN_DT}+0.5);
my(@elapsed,@so,@mad,%nBest,%madBest);
my($n_valid_windows) = 0;
$first_ens = $approx_joint_profile_start_ens
if ($first_ens < $approx_joint_profile_start_ens);
my($last_lag_piece) = ($last_ens == $lastGoodEns); # none is following
$last_ens = $approx_joint_profile_end_ens
if ($last_ens > $approx_joint_profile_end_ens);
for (my($wi)=0; $wi<$n_windows; $wi++) {
my($fe) = $first_ens + int(($last_ens-$first_ens-$window_ens)*$wi/($n_windows-1)+0.5);
my($so,$mad) = bestLag($fe,$fe+$window_ens,$search_radius,$scan_increment);
$elapsed[$wi] = $LADCP{ENSEMBLE}[$fe+int($w_size/2/$LADCP{MEAN_DT}+0.5)]->{ELAPSED};
die("assertion failed\nfe=$fe, lastGoodEns=$lastGoodEns, w_size=$w_size") unless ($elapsed[$wi]);
next unless ($mad < 9e99);
$so[$wi] = $so; $mad[$wi] = $mad;
$n_valid_windows++;
$nBest{$so}++; $madBest{$so} += $mad;
}
foreach my $i (keys(%nBest)) {
$madBest{$i} /= $nBest{$i};
}
my($med_mad) = median(values(%madBest)); # remove lags with large mads
my($mad_mad) = mad2($med_mad,values(%madBest));
foreach my $lag (keys(%nBest)) {
next if ($madBest{$lag} <= $med_mad+$mad_mad);
$n_valid_windows -= $nBest{$lag};
$nBest{$lag} = 0;
}
my(@best_lag);
foreach my $lag (keys(%nBest)) {
$best_lag[0] = $lag if ($nBest{$lag} > $nBest{$best_lag[0]});
}
foreach my $lag (keys(%nBest)) {
next if ($lag == $best_lag[0]);
$best_lag[1] = $lag if ($nBest{$lag} > $nBest{$best_lag[1]});
}
foreach my $lag (keys(%nBest)) {
next if ($lag == $best_lag[0] || $lag == $best_lag[1]);
$best_lag[2] = $lag if ($nBest{$lag} > $nBest{$best_lag[2]});
}
if ($nBest{$best_lag[2]}) {
progress("\t3 most popular offsets: %d (%d%% %.1fcm/s mad), %d (%d%% %.1fcm/s mad), %d (%d%% %.1fcm/s mad)\n",
$best_lag[0],int(($nBest{$best_lag[0]}/$n_valid_windows)*100+0.5),100*$madBest{$best_lag[0]},
$best_lag[1],int(($nBest{$best_lag[1]}/$n_valid_windows)*100+0.5),100*$madBest{$best_lag[1]},
$best_lag[2],int(($nBest{$best_lag[2]}/$n_valid_windows)*100+0.5),100*$madBest{$best_lag[2]});
} elsif ($nBest{$best_lag[1]}) {
progress("\toffsets: %d (%d%% %.1fcm/s mad), %d (%d%% %.1fcm/s mad)\n",
$best_lag[0],int(($nBest{$best_lag[0]}/$n_valid_windows)*100+0.5),100*$madBest{$best_lag[0]},
$best_lag[1],int(($nBest{$best_lag[1]}/$n_valid_windows)*100+0.5),100*$madBest{$best_lag[1]});
} else {
progress("\toffset: %d (%d%% %.1fcm/s mad)\n",
$best_lag[0],int(($nBest{$best_lag[0]}/$n_valid_windows)*100+0.5),100*$madBest{$best_lag[0]});
}
unless ($nBest{$best_lag[0]}+$nBest{$best_lag[1]}+$nBest{$best_lag[2]} >= $opt_3*$n_valid_windows) {
if (max(@best_lag)-min(@best_lag) > $TL_max_allowed_three_lag_spread) {
warning(2,"$0: cannot determine a valid $ctmsg lag; top 3 tags account for %d%% of total (use -3 to relax criterion)\n",
int(100*($nBest{$best_lag[0]}+$nBest{$best_lag[1]}+$nBest{$best_lag[2]})/$n_valid_windows+0.5));
$failed = 1;
} else {
warning(1,"top 3 tags account for only %d%% of total\n",
int(100*($nBest{$best_lag[0]}+$nBest{$best_lag[1]}+$nBest{$best_lag[2]})/$n_valid_windows+0.5));
}
}
my($bmo) = $best_lag[0];
if ($bmo > 0.9*$search_radius/2/$CTD{DT}) {
if ($search_radius == $w_size) {
warning(0,"lag too close to edge of search --- trying again after shifting the initial offset\n");
$CTD{TIME_LAG} += $search_radius/2;
} else {
warning(0,"lag too close to edge of search --- trying again after doubling the search radius\n");
$search_radius *= 2;
$search_radius =- $w_size if ($search_radius > $w_size);
}
undef(%nBest); undef(%madBest); undef(@best_lag);
goto RETRY;
}
if (-$bmo > 0.9*$search_radius/2/$CTD{DT}) {
if ($search_radius == $w_size) {
warning(0,"lag too close to edge of search --- trying again after shifting the initial offset\n");
$CTD{TIME_LAG} -= $search_radius/2;
} else {
warning(0,"lag too close to edge of search --- trying again after doubling the search radius\n");
$search_radius *= 2;
$search_radius =- $w_size if ($search_radius > $w_size);
}
undef(%nBest); undef(%madBest); undef(@best_lag);
goto RETRY;
}
if (@out_TL && $scan_increment==1) {
push(@elapsed_buf,@elapsed); # buffer elapsed data in static scope
push(@so_buf,@so); # scan offset
push(@mad_buf,@mad); # mean absolute deviation
push(@bmo_buf,$bmo); # best median offset
push(@te_buf,$elapsed[$#elapsed]); # to elapsed (from elapsed to elapsed, capisc?)
$elapsed_min_buf = $elapsed[0] # min of valid elapsed (for plotting)
unless defined($elapsed_min_buf);
if ($last_lag_piece) { # output all data
progress("\tWriting time-lagging time series to ");
my($saveParams) = $antsCurParams;
@antsNewLayout = ('elapsed.LADCP','scan_offset','mad','downcast');
&antsAddParams('best_scan_offsets',"@bmo_buf");
&antsAddParams('to_elapsed_limits',"@te_buf");
&antsAddParams('elapsed.min',$elapsed_min_buf);
&antsAddParams('elapsed.max',$elapsed_buf[$#elapsed_buf]);
&antsAddParams('elapsed.bot',$LADCP{ENSEMBLE}[$LADCP_atbottom]->{ELAPSED});
foreach my $of (@out_TL) {
progress("<$of> ");
$of = ">$of" unless ($of =~ /^$|^\s*\|/);
open(STDOUT,$of) || error("$of: $!\n");
undef($antsActiveHeader) unless ($ANTS_TOOLS_AVAILABLE);
for (my($wi)=0; $wi<@elapsed_buf; $wi++) {
&antsOut($elapsed_buf[$wi],$so_buf[$wi],$mad_buf[$wi],
($elapsed_buf[$wi]<$LADCP{ENSEMBLE}[$LADCP_atbottom]->{ELAPSED}));
}
&antsOut('EOF'); open(STDOUT,">&2");
}
$antsCurParams = $saveParams;
progress("\n");
}
}
return defined($failed) ? undef : $CTD{TIME_LAG}+$bmo*$CTD{DT};
}
} # STATIC SCOPE
1;