#!/usr/bin/env perl
# -*- perl -*- 
#-----------------------------------------------------------------------
#   Module Name:    $Source: /Users/goeke/programming/perl/crater/RCS/ar_zero,v $
#   Purpose:        Receive CCSDS packets and strip out data
#   Language:       Perl 5
#   Assumptions:    Consistent with Data ICD, 32-02001
#   Part Number:    
#   Author:         Robert F. Goeke (goeke@space.mit.edu
#   References:     
#   Copyright:      Massachusetts Institute of Technology 2008
#-----------------------------------------------------------------------

########################################################################
# Check the zero crossing value of the science transfer function
########################################################################

$DIR = $ENV{CRATERTOOLS};
$LOWAMP  = 64;         # command is 8:64
$HIGHAMP = 128;        # command is 8:128
# $ECHO      = 2;
$CMDVALUE  = 'LastValue';   # This is rtlm standard ASCII output
$STARTECHO = "19200";       # 0x4B00;
$STARTDATA = "512";         # 0x0200;
# $ENDLOW    = 0x00F1;
# $ENDHIGH   = 0x00F2;
$STOPECHO  = 0xFFFF;
$EVENTS    = 'EventAmp';

$Verbose = 0;
$InputFiles = '';
$SAMPLES = 4000;     # In 10 sec we get about 20,000 samples
$OFF = 20;           # noise offset/margin

########################################################################
#  The master program is here
########################################################################

&Setup;
&Run;
exit 0;

########################################################################
########################################################################

########################################################################
# Help message
########################################################################
sub Help {

    print STDOUT "Usage: $0 [-h] [-q] [-v] file1 [file2 ...]

Processes LRO spacecraft data to extract zero-crossing results

flag  -h    prints out this help message
      -q    quick scan of data; ignores initial echo tags
      -v    verbose operation
";

}

########################################################################
# Run the program
########################################################################
sub Run {
    my (@high,@low,@noise,$ii);

    if (!$Quick) {
	while (<GET>) {             # skip to beginning of the test
	    next if ($_ !~ /$CMDVALUE\s+$STARTECHO/);
	    print STDERR "### Found zero_cross test\n" if $Verbose;
	    last;
	} 
	if (!$_) {
	    print STDERR "ERR: Test title marker $STARTECHO not found\n";
	    exit 5;
	}
    }

    while (<GET>) {             # skip to first data collection
	next if ($_ !~ /$CMDVALUE\s+$STARTDATA/);
	print STDERR "### Start data low collection\n" if $Verbose;
	last;
    }
    if (!$_) {
	print STDERR "ERR: Low Cal data sync $STARTDATA not found\n";
	exit 3;
    }

#    @low = &Stat;         # extra pause does not seem necessary
    @low = &Stat;
    @noise = splice(@low,6,6);
    
    while (<GET>) {
	next if ($_ !~ /$CMDVALUE\s*$STARTDATA/);
	print STDERR "### Start data high collection\n" if $Verbose;
	last;
    } 
    if (!$_) {
	print STDERR "ERR: High Cal data sync $STARTDATA not found\n";
	exit 3;
    }

#    @high = &Stat;
    @high = &Stat;

    print "Detector:    1       2       3       4       5       6\n";
    printf STDOUT "High:  %8.1f%8.1f%8.1f%8.1f%8.1f%8.1f\n", @high;
    printf STDOUT "Low:   %8.1f%8.1f%8.1f%8.1f%8.1f%8.1f\n", @low;
    printf STDOUT "Noise: %8.1f%8.1f%8.1f%8.1f%8.1f%8.1f\n", @noise;

    printf STDOUT "Offset:";
    for ($ii=0; $ii<6; $ii++) {
	printf STDOUT "%8.1f",
	($LOWAMP*$high[$ii]-$HIGHAMP*$low[$ii])/($LOWAMP-$HIGHAMP);
    }
    printf STDOUT "\n";
}

########################################################################
# Setup the program
########################################################################
sub Setup {
    $Quick = 0;
    my $foo;
    while ($foo = shift(@ARGV)) {
	if ($foo =~ /^-[hH]/) {
	    &Help;
	    exit 0;
	}
	if ($foo =~ /^-[qQ]/) {
	    $Quick++;             # don't insist on Title marker
	    next;
	}
	if ($foo =~ /^-[vV]/) {
	    $Verbose++;
	    next;
	}
	if ($foo =~ /^-/) {
	    print STDERR "Unknown flag $foo\n";
	    &Help;
	    exit 1;
	}
	if (-r $foo) {
	    $InputFiles = $InputFiles . "$foo ";
	    next;
	} else {
	    print STDERR "Could not read $foo as input\n";
	    exit 2;
	}
    }

    if (!$InputFiles) {
	print STDERR "$0 requires at least one input file name\n";
	&Help;
	exit 2;
    }

    open(GET,"$DIR/browse -f - $InputFiles | 
          $DIR/rtlm -r - -a -t |");
}

########################################################################
# Calculate the means with noise rejection
# Cribbed from "statistics"
########################################################################
sub Stat {
    my $index = $_[1];
    my ($ii,$jj,$q,$name,$one,$two,$three,$four,$five,$six);
    my (@sum,@square,$rejects,$base);

    $jj = 0;              # total event counter
    $q = $OFF;            # match requirement for noise rejection
    $base = 0;            # when 0 we calulate the current mean
                          #   to be used following time for noise rejection
    $rejects = 0;

    while (<GET>) {
	next if ($_ !~ /$EVENTS/);
	$jj++;
	my ($name,$one,$two,$three,$four,$five,$six) = split;

	if (!$base) {        # First time through
	    $sum[1] += $one;
	    $sum[2] += $two;
	    $sum[3] += $three;
	    $sum[4] += $four;
	    $sum[5] += $five;
	    $sum[6] += $six;

	    if ($jj>=$SAMPLES) {    # End of reference work
		print STDERR "### Done with baseline\n" if $Verbose;

		$mone   = $sum[1]/$SAMPLES - $OFF;
		$mtwo   = $sum[2]/$SAMPLES - $OFF;
		$mthree = $sum[3]/$SAMPLES - $OFF;
		$mfour  = $sum[4]/$SAMPLES - $OFF;
		$mfive  = $sum[5]/$SAMPLES - $OFF;
		$msix   = $sum[6]/$SAMPLES - $OFF;
	    
		$sum[1]=$sum[2]=$sum[3]=$sum[4]=$sum[5]=$sum[6]=0;

		if ($Verbose) {
		    print STDERR "### means-$OFF: $mone $mtwo $mthree $mfour $mfive $msix\n";
		}
		$jj = 0;            # reset event counter
		$base++;            # quit conditioning phase
	    }

	} else {               # only do this second time through
	    if  ( $one<$mone || $two<$mtwo || $three<$mthree ||
		  $four<$mfour || $five<$mfive || $six<$msix ) {
		$jj--; $rejects++;
		next;        # noise rejection
	    }
	    $sum[1] += $one;
	    $sum[2] += $two;
	    $sum[3] += $three;
	    $sum[4] += $four;
	    $sum[5] += $five;
	    $sum[6] += $six;
    
	    $square[1] += $one * $one;
	    $square[2] += $two * $two;
	    $square[3] += $three * $three;
	    $square[4] += $four * $four;
	    $square[5] += $five * $five;
	    $square[6] += $six * $six;

	    last if ($jj>=$SAMPLES);   # keep adding until we get enough data
	}
    }            # end of while(<GET>)
	
    printf STDERR "### %d samples/%d rejected\n", 
           $jj, $rejects if ($Verbose);

    return if (!$jj);    # Avoids divide-by-zero error

    for ($ii=1; $ii<=6; $ii++) {
	$mean[$ii] = $sum[$ii]/$jj;
	$sigma[$ii] = sqrt($square[$ii]/$jj - $mean[$ii]*$mean[$ii]);
    }

    splice(@mean,0,1);            # because above we ran 1..6
    splice(@sigma,0,1);           #   and we want to pass 0..5
    splice(@mean,6,0,@sigma);     # tacks @sigma on end of @mean

    return(@mean);
}
    

########################################################################
# Pod follows
########################################################################

=for html 
<head><title>CRaTER -- lf_zero</title></head>

=head2 NAME

B<lf_zero> -- Calculate zero offset of each CRaTER detector chain

=head2 USAGE

     lf_zero [-h] [-v] filename1 [filename2 ...]

=head2 FLAGS

     -h    provides help message
     -q    quick mode; ignores initial echo tags
     -v    verbose mode

=head2 DESCRIPTION

This script assumes the existance of one or more files which contain
   the data from a zero-crossing test.  The script collects the data
   file with B<browse> and pipes the data through B<rtlm> before 
   searching for echo data markers and then doing the math.

The script takes 4000 science data points (about 2 seconds worth) at
   two different internal cal values and calculates the extrapolated 
   zero crossing point (which, because the electronics is detecting
   the peak signal + noise, tends always to be positive).  The RMS
   noise present on the (low) internal cal signal is also displayed.

=head2 DATA MARKERS required

=over

=item 0x4B00 -- start of test

=item 0x0200 -- start of each data run

=back

=head2 ENVIRONMENT

    perl5.002     Minimum version of Perl interpreter required
    CRATERTOOLS   Environment variable containing path to CRaTER utilities
    CRATER_GSE    Environment variable containing EGSE machine name

=head2 BUGS

The internal calibration signals have non-linearities, Cal High much
    worse than Cal Low.  We therefore base the zero offset
    calculations on two values below 10% of full scale.  

=head2 SEE ALSO

lf_zero, browse, rtlm

=head2 AUTHOR

Bob Goeke

=head2 RCS Information

$Id: ar_zero,v 1.4 2008/04/11 18:42:31 goeke Exp goeke $

=cut

########################################################################
# history follows
########################################################################
# $Log: ar_zero,v $
# Revision 1.4  2008/04/11 18:42:31  goeke
# Added rms noise calculations
#
# Revision 1.3  2008/04/11 14:15:01  goeke
# Take out start/stop flags for browse
# Fix help and documentation
# Add -q flag and fix logic
#
# Revision 1.2  2008/04/09 19:02:47  goeke
# Working version
#
# Revision 1.1  2008/04/08 19:04:44  goeke
# Initial revision
#
# Revision 1.4  2007/11/14 16:43:40  goeke
# Reverse order of high/low report
#
# Revision 1.3  2007/08/17 14:40:58  goeke
# Minor cleanups
#
# Revision 1.2  2007/04/17 12:16:35  goeke
# Bug fixes; add POD
#
# Revision 1.1  2007/04/13 19:22:38  goeke
# Initial revision
#
#