new file mode 100755
--- /dev/null
+++ b/patchPD0
@@ -0,0 +1,158 @@
+#!/usr/bin/perl
+#======================================================================
+# P A T C H P D 0
+# doc: Tue Aug 23 20:00:15 2016
+# dlm: Mon Nov 20 12:27:15 2017
+# (c) 2010 A.M. Thurnherr
+# uE-Info: 32 16 NIL 0 0 72 0 2 4 NIL ofnI
+#======================================================================
+
+$antsSummary = 'patch TRDI PD0 file with external attitude data';
+
+# History:
+# Aug 23, 2016: - exported from IMP+LADCP
+# Aug 25, 2016: - completed basic structure
+# Nov 20, 2017: - major code cleanup
+# - added -d) to keep original data source id
+
+# PATCH-FILE REQUIREMENTS (ANTS format)
+# - %LADCP_pitch.mu %LADCP_roll.mu mean LADCP pitch and roll
+# - %IMU_hdg_offset heading offset of external IMU
+# - LADCP_ens ADCP ensemble number
+# - pitch, roll external pitch/roll *anomalies*
+# - hdg external heading rotated into ADCP coord system
+
+# PATCHED PD0 FILE:
+#
+# - pitch = RDI_pitch(mean_LADCP_gimbal_pitch + rotated_external_pitch_anomaly)
+# - roll = mean_LADCP_roll + rotated_external_roll_anomaly
+# - hdg = external_hdg - heading_offset
+#
+# - unless -d is used, every patched ensemble has set the DATA_SOURCE_ID as follows;
+# PROCESSING SOFTWARE NEEDS TO BE ABLE TO DEAL WITH DSID values != 0x7F
+# 0xA0 no values patched
+# 0xA1 heading patched
+# 0xA2 roll patched
+# 0xA3 roll & heading patched
+# 0xA4 pitch patched
+# 0xA5 pitch & heading patched
+# 0xA6 pitch & roll patched
+# 0xA7 pitch, roll & heading patched
+#
+# - additionally, all velocities from ensembles with missing pitch/roll/heading
+# values are removed unless -k is set
+
+($ANTS) = (`which ANTSlib` =~ m{^(.*)/[^/]*$});
+($ADCP_TOOLS) = ($0 =~ m{^(.*)/[^/]*$});
+
+$antsMinLibVersion = 6.7;
+$ADCP_tools_minVersion = 1.8;
+
+require "$ANTS/ants.pl";
+require "$ANTS/libvec.pl";
+require "$ANTS/libstats.pl";
+require "$ADCP_TOOLS/ADCP_tools_lib.pl";
+
+$antsParseHeader = 0;
+&antsUsage('dhko:pr',2,
+ '[patch -p)itch] [-r)oll] [-h)eading] (none patches all)',
+ '[-o) <heading-offset>] [-k)eep velocities of unpatched ensembles]',
+ '[keep original -d)ata-source id]',
+ '<original PD0 file> <patched PD0 file> [external attitude file]');
+
+$opt_p = $opt_r = $opt_h = 1
+ unless ($opt_p || $opt_r || $opt_h);
+
+$LADCP_file = &antsFileArg();
+$outPD0 = $ARGV[0]; shift;
+
+#----------------------------------------------------------------------
+# Step 1: Read LADCP Data
+#----------------------------------------------------------------------
+
+readData($LADCP_file,\%LADCP);
+
+#----------------------------------------------------------------------
+# Step 2: Process External Attidue Input to Patch PD0 file
+#----------------------------------------------------------------------
+
+my($pr_missing,$hdg_missing) = (0,0);
+
+&antsIn();
+
+my($ensF) = &fnr('LADCP_ens');
+my($pitchF) = &fnr('pitch');
+my($rollF) = &fnr('roll');
+my($hdgF) = &fnr('hdg');
+my($LADCP_pitch_mean) = &antsRequireParam('LADCP_pitch.mu');
+my($LADCP_roll_mean) = &antsRequireParam('LADCP_roll.mu');
+
+my($rho,$crho,$srho);
+if (defined($opt_o)) {
+ $rho = $opt_o - &antsRequireParam('IMU_hdg_offset');
+ $crho = cos(rad($rho));
+ $srho = sin(rad($rho));
+}
+
+do {
+ my($ens) = $P{RECNO};
+ die("assertion failed [$ants_[0][$ensF] != $LADCP{ENSEMBLE}[$ens]->{NUMBER} --- 1-$LADCP{ENSEMBLE}[0]->{NUMBER} + $P{RECNO} + $d]")
+ unless ($ants_[0][$ensF] == $LADCP{ENSEMBLE}[$ens]->{NUMBER});
+# print(STDERR "assertion succeeded [$ants_[0][$ensF] == $LADCP{ENSEMBLE}[$ens]->{NUMBER} --- 1-$LADCP{ENSEMBLE}[0]->{NUMBER} + $P{RECNO} + $d]\n");
+ $LADCP{ENSEMBLE}[$ens]->{DATA_SOURCE_ID} = 0xA0;
+
+ if (numbersp($ants_[0][$pitchF],$ants_[0][$rollF])) {
+ if (defined($opt_o)) {
+ my($rot_p) = ($ants_[$r][$pitchF] * $crho +
+ $ants_[$r][$rollF] * $srho);
+ my($rot_r) = (-$ants_[$r][$pitchF] * $srho +
+ $ants_[$r][$rollF] * $crho);
+ $ants_[$r][$pitchF] = $rot_p;
+ $ants_[$r][$rollF] = $rot_r;
+ }
+ if ($opt_p) {
+ $LADCP{ENSEMBLE}[$ens]->{DATA_SOURCE_ID} |= ($opt_p<<2);
+ $LADCP{ENSEMBLE}[$ens]->{PITCH} = RDI_pitch($LADCP_pitch_mean + $ants_[0][$pitchF],
+ $LADCP_roll_mean + $ants_[0][$rollF]);
+ }
+ if ($opt_r) {
+ $LADCP{ENSEMBLE}[$ens]->{DATA_SOURCE_ID} |= ($opt_r<<1);
+ $LADCP{ENSEMBLE}[$ens]->{ROLL} = $LADCP_roll_mean + $ants_[0][$rollF];
+ }
+ } else {
+ $pr_missing++;
+ unless ($opt_k) {
+ clearEns(\%LADCP,$ens);
+ $LADCP{ENSEMBLE}[$ens]->{DATA_SOURCE_ID}= 0xA0;
+ }
+ }
+
+ if (numberp($ants_[0][$hdgF])) {
+ $LADCP{ENSEMBLE}[$ens]->{DATA_SOURCE_ID} |= $opt_h;
+ if (defined($opt_o)) {
+ $ants_[0][$hdgF] -= $rho;
+ $ants_[0][$hdgF] += 360 if ($ants_[0][$hdgF] < 0);
+ }
+ $LADCP{ENSEMBLE}[$ens]->{HEADING} = $ants_[0][$hdgF]
+ if $opt_h;
+ } else {
+ $hdg_missing++;
+ unless ($opt_k) {
+ clearEns(\%LADCP,$ens);
+ $LADCP{ENSEMBLE}[$ens]->{DATA_SOURCE_ID}= 0xA0;
+ }
+ }
+} while (&antsIn());
+
+$LADCP{ENSEMBLE}[0]->{DATA_SOURCE_ID} = 0x7F; # ensure correct DSID (1st ens: orig; 2nd ens: this prog)
+$LADCP{ENSEMBLE}[1]->{DATA_SOURCE_ID} = 0xA0
+ unless ($LADCP{ENSEMBLE}[1]->{DATA_SOURCE_ID}&0xF0 == 0xA0);
+
+writeData($outPD0,\%LADCP);
+
+my($verb) = $opt_k ? 'retained' : 'cleared';
+printf(STDERR "$outPD0: %d pitch/roll & %d heading values $verb\n",$pr_missing,$hdg_missing)
+ if ($pr_missing+$hdg_missing);
+
+exit(0);
+