first commit

Author: chriswolfvision

ec

@@ -0,0 +1,104 @@
+#!/usr/bin/ruby
+# **************************************************************************
+# ec (say "extract column")
+# Written by Christian Wolf
+#
+# This program is free software; you can redistribute it and/or modify  
+# it under the terms of the GNU General Public License as published by  
+# the Free Software Foundation; either version 2 of the License, or     
+# (at your option) any later version.                                   
+#                                                                         
+# This program is distributed in the hope that it will be useful,       
+# but WITHOUT ANY WARRANTY; without even the implied warranty of        
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         
+# GNU General Public License for more details.                          
+#                                                                         
+# You should have received a copy of the GNU General Public License     
+# along with this program; if not, write to the                         
+# Free Software Foundation, Inc.,                                       
+# 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.   
+#
+# **************************************************************************
+#
+# Changelog:
+# 2.1  21.06.2009: Included range processing, i.e. columns 1-16
+# 2.0  13.10.2005: Port to the ruby programming language
+# 1.0  03.07.2005: changed syntax: allow multiple rows to be selected
+# 0.5  xx.xx.2002: start of project
+# **************************************************************************
+
+$Version="2.1 21.06.2009"
+
+$help=<<END_MESSAGE
+ec is a tool which is able to extract columns from a text file. Just pipe 
+your data through the ec command and specify the column indices as arguments
+(columns begin with 1), e.g.:
+
+cat data.txt | ec 2 3 
+
+Ranges can be specified using the dash operator, i.e. 4-7. Do not put
+whitespace before and after the dash. The starting and endpoint need to
+be specified, i.e. -3 or 7- are not allowed.
+	
+ec is also usefull if the columns in the original file are not separated by 
+whitespace but by another character. The character separater used by ec 
+can configured by adding it on the command line preceeded by a dash. 
+The output character separater is always whitespace. If, for example, 
+you have a file whose columns are seperated by a semicolon and you want to 
+plot columns 5 and 3, use the command:
+
+cat data.txt | ec -; 5 3
+
+License: GPL; this is free software. There is absolutely NO warranty!!
+END_MESSAGE
+
+# ---- The usage message
+def usage
+	printf "usage: %s [ -<separator> ] { <column-number> }\n",$0
+	printf "\n%s\n",$help
+	exit 1
+end
+
+# ---- the main program
+def main
+	
+	# ---- Check Arguments
+	usage if ARGV.length < 1
+	usage if ARGV[0]=="-h"
+	if ARGV[0]=="-v"
+		printf "ec version %s\n",$Version
+		printf "Written by Christian Wolf\n"
+		printf "License: GPL; this is free software. "
+		puts "There is absolutely NO warranty!!"
+		exit 0
+	end
+	
+	# ---- Create the delimiter
+	delimiter=" "
+	delimiter=ARGV[0][1,ARGV[0].length-1] if ARGV[0][0,1]=="-"
+	
+	# ---- Create the array with separator indices
+	indices=[]
+	ARGV.each do |x| 
+	   if x[0,1]!="-"
+	       pos=x.index("-") 
+	       if pos==nil
+	           indices.push(x.to_i-1) 
+	       else
+	           ibeg=x[0,pos].to_i
+	           iend=x[pos+1,x.length-pos].to_i
+	           (ibeg..iend).each { |y| indices.push(y-1) }
+	       end
+	   end
+	end
+	
+	# ---- Traverse the lines
+	while line = $stdin.gets
+		line["\n"]=""
+		arr=line.split(delimiter)
+		indices.each { |i| printf "%s ",arr[i] }
+		puts
+	end
+end
+
+main