minor code cleanup for human formatting

[barcat.git] / barcat

diff --git a/barcat b/barcat
index 69f4516c0fbd766defefe578e9cb6e8eb4cd1efc..00a21739671c0a4d00df95517912299cdd472757 100755 (executable)
--- a/barcat
+++ b/barcat
@@ -17,7 +17,12 @@ my %opt;
 GetOptions(\%opt,
        'color|c!',
        'C' => sub { $opt{color} = 0 },
-       'field|f=s',
+       'field|f=s' => sub {
+               eval {
+                       local $_ = $_[1];
+                       $opt{anchor} = /^[0-9]+$/ ? qr/(?:\S*\h+){$_}\K/ : qr/$_/;
+               } or die $@ =~ s/(?: at .+)?$/ for option $_[0]/r;
+       },
        'human-readable|H!',
        'interval|t:i',
        'trim|length|l=s' => sub {
@@ -51,7 +56,9 @@ GetOptions(\%opt,
 $opt{width} ||= $ENV{COLUMNS} || 80;
 $opt{color} //= -t *STDOUT;  # enable on tty
 $opt{trim}   *= $opt{width} / 100 if $opt{trimpct};
-$opt{units}   = $opt{'human-readable'} && ['', qw( k M G T <> n μ m )];
+$opt{units}   = [split //, ' kMGTPEZYyzafpnμm'] if $opt{'human-readable'};
+$opt{anchor} //= qr/\A/;
+$opt{'value-length'} = 6 if $opt{units};
 
 if (defined $opt{interval}) {
        $opt{interval} ||= 1;
@@ -65,13 +72,11 @@ if (defined $opt{interval}) {
 $SIG{INT} = 'IGNORE';  # continue after assumed eof
 
 my (@lines, @values);
-my $anchor = !defined $opt{field} ? qr/\A/ :
-       $opt{field} =~ /^[0-9]+$/ ? qr/(?:\S*\h+){$opt{field}}\K/ :
-       $opt{field};
+my $valmatch = qr/$opt{anchor} ( \h* -? [0-9]* \.? [0-9]+ (?: e[+-]?[0-9]+ )? |)/x;
 while (readline) {
        s/\r?\n\z//;
        s/^\h*// unless $opt{unmodified};
-       push @values, s/$anchor ( \h* -? [0-9]* \.? [0-9]+ |)/\n/x && $1;
+       push @values, s/$valmatch/\n/ && $1;
        if (defined $opt{trim}) {
                my $trimpos = abs $opt{trim};
                if ($trimpos <= 1) {
@@ -127,7 +132,13 @@ if ($opt{markers} // 1 and $size > 0) {
 
 sub sival {
        my $unit = int(log($_[0]) / log(1000) - ($_[0] < 1));
-       sprintf "%3.1f%1s", $_[0] / 1000 ** $unit, $opt{units}->[$unit];
+       my $float = $_[0] !~ /^ (?: 0*\.)? [0-9]{1,3} $/x;
+       sprintf('%*.*f%*s',
+               $float ? 5 : 3, $float,  # length and tenths
+               $_[0] / 1000 ** $unit,   # number
+               $float ? 0 : 3,          # unit size
+               $#{$opt{units}} >> 1 < abs $unit ? "e$unit" : $opt{units}->[$unit]
+       );
 }
 
 while ($nr <= $#lines) {
@@ -194,6 +205,8 @@ for example I<-f'(\d+)'> for the first digits anywhere.
 
 Format values using SI unit prefixes,
 turning long numbers like I<12356789> into I<12.4M>.
+Also changes an exponent I<1.602176634e-19> to I<160.2z>.
+Short integers are aligned but kept without decimal point.
 
 =item -t, --interval[=<seconds>]