From 3b0b3782495e65d7007135896e81d878fae64198 Mon Sep 17 00:00:00 2001
From: Ole Tange <ole@tange.dk>
Date: Wed, 20 Jan 2021 22:55:31 +0100
Subject: [PATCH] plotpipe: --smooth implemented.

---
 plotpipe/README   |  4 +--
 plotpipe/plotpipe | 72 +++++++++++++++++++++++++++++++++++++++++------
 2 files changed, 66 insertions(+), 10 deletions(-)

diff --git a/plotpipe/README b/plotpipe/README
index d535157..7bdac30 100644
--- a/plotpipe/README
+++ b/plotpipe/README
@@ -32,8 +32,8 @@ Examples:
      printf "Column1\tColumn2\tColumn3";
      paste <(seq 1 100) <(seq 1 100) <(seq 1 100 | shuf) ) | plotpipe
 
-Copyright (C) 2020 Ole Tange, http://ole.tange.dk and Free Software
-Foundation, Inc.
+Copyright (C) 2020-2021 Ole Tange, http://ole.tange.dk and Free
+Software Foundation, Inc.
 
 License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
 This is free software: you are free to change and redistribute it.
diff --git a/plotpipe/plotpipe b/plotpipe/plotpipe
index 369a7fc..a3b78f5 100755
--- a/plotpipe/plotpipe
+++ b/plotpipe/plotpipe
@@ -72,6 +72,13 @@ used as x-value. B<--nox> will use line number as x-value.
 Use \0 (NUL) instead of newline (\n) as record separator.
 
 
+=item B<--smooth> I<width>
+
+=item B<-s> I<width>
+
+Smooth values. Take the average of I<width> y-values.
+
+
 =item B<--version>
 
 =item B<-V>
@@ -192,6 +199,7 @@ sub options_hash() {
 	 "null|0" => \$opt::null,
 	 "nox|n" => \$opt::nox,
 	 "header|H" => \$opt::header,
+	 "smooth|s=i" => \$opt::smooth,
 	);
 }
 
@@ -223,6 +231,9 @@ sub help() {
 	 '-0      Records separated by \0 instead of \n',
 	 '-C str  Columns separator',
 	 '-V      Show version',
+	 '--logx/logy/logxy Log x/y/x&y',
+	 '-n      No X value',
+	 '-s num  Smooth num Y-values',
 	 "",
 	 "See 'man $Global::progname' for details",
 	 "",);
@@ -279,6 +290,18 @@ sub my_dump(@) {
     }
 }
 
+sub sum(@) {
+    # Returns:
+    #   Sum of values of array
+    my @args = @_;
+    my $sum = 0;
+    for (@args) {
+        # Skip undefs
+        $_ and do { $sum += $_; }
+    }
+    return $sum;
+}
+
 sub max(@) {
     # Returns:
     #   Maximum value of array
@@ -359,30 +382,63 @@ if($opt::header) {
     @header = ();
 }
 
-# Save data to tmpfile that will be read by Gnuplot
-use File::Temp qw(tempfile);
-$ENV{'TMPDIR'} ||= "/tmp";
-my($filehandle,$filename) =
-    tempfile(DIR=>$ENV{'TMPDIR'}, TEMPLATE => 'plotXXXXX');
+# Convert input to perl table
 my $ncols = split /$opt::colsep/, $csv[0];
+my @tbl;
 if($ncols >= 2 and not $opt::nox) {
     # Column 1 = x-axis
     for(@csv) {
 	chomp;
-	print $filehandle ((join "\001", split /$opt::colsep/, $_),"\n");
+	my @row = split /$opt::colsep/, $_;
+	push @tbl,\@row;
     }
 } else {
     # All data = y-axis, invent x-axis
     my $x = 0;
     for(@csv) {
 	chomp;
-	print $filehandle ((join "\001", $x++, split /$opt::colsep/, $_),"\n");
+	my @row = ($x++, split /$opt::colsep/, $_);
+	push @tbl,\@row;
     }
     # Prepend dummy header for x-axis
     unshift(@header,"");
     $ncols += 1;
 }
 
+# Smooth data
+if($opt::smooth) {
+    my (@sum,@new);
+    if($#tbl < $opt::smooth) {
+	print STDERR "plotpipe: --smooth must be lower than the ",
+	    "number of rows (",1+$#tbl,")\n";
+	exit(255);
+    }
+    my $smooth = $opt::smooth-1;
+    for(my $x = 0; $x < $smooth; $x++) {
+	for (my $y = 0; $y <= $#{$tbl[$x]}; $y++) {
+	    $sum[$y] += $tbl[$x][$y] / $opt::smooth;
+	}
+    }
+    for(my $x = $smooth; $x <= $#tbl; $x++) {
+	for (my $y = 0; $y <= $#{$tbl[$x]}; $y++) {
+	    $sum[$y] += $tbl[$x][$y] / $opt::smooth;
+	    $new[$x-$smooth][$y] = $sum[$y];
+	    $sum[$y] -= $tbl[$x-$smooth][$y] / $opt::smooth;
+	}
+    }
+    @tbl = @new;
+}
+
+# Save data to tmpfile that will be read by Gnuplot
+use File::Temp qw(tempfile);
+$ENV{'TMPDIR'} ||= "/tmp";
+my($filehandle,$filename) =
+    tempfile(DIR=>$ENV{'TMPDIR'}, TEMPLATE => 'plotXXXXX');
+for(@tbl) {
+    print $filehandle (join "\001", @$_)."\n";
+}
+close $filehandle;
+
 # Generate the variant part of Gnuplot script
 for(my $col = 2; $col <= $ncols; $col++) {
     my $legend;
@@ -392,6 +448,7 @@ for(my $col = 2; $col <= $ncols; $col++) {
     push @plotscript, qq("$filename" using 1:$col with lines $legend,);
 }
 
+# Add --logx/--logy/--logxy to Gnuplot script
 my @logscale;
 if($opt::logx or $opt::logxy) {
     push @logscale, "set logscale x 10;";
@@ -400,7 +457,6 @@ if($opt::logy or $opt::logxy) {
     push @logscale, "set logscale y 10;";
 }
     
-
 # Make full Gnuplot script
 my $plotscript=<<_EOS ;
 set title "@title";