Hi cool rubyers: I'm sorry but my little brain is stuck w my first ruby program. The program's objective is to move the "-" sign of negative numbers to the front ;eg, fr 999.99- to -999.99 so I run: C:\family\ruby>ruby negatives.rb negatives.txt and the output is: 99.99- 9999- 99-99 99-99- 99999.99- 9.99- >>-99.99<< >>-9999<< >>-99<<99 >>-99<<>>-99<< >>-99999.99<< >>-9.99<< My program (regex actually) works for figures even of the form 9999-999 or 99-99-. I do NOT want this since these numbers may be dates, telno, etc... So how do I restrict my regex so that it will only process numbers of the form 999- or 999.99- but not 999-999 or 999-99- the file contents of negatives.rb and negatives.txt follow below. Many thanks for the help, -botp w small brain... #------------------- #negatives.txt 99.99- 9999- 99-99 99-99- 99999.99- 9.99- #------------------- #negatives.rb File.open(ARGV[0]) do |f| f.each do |line| puts line puts (line.gsub ( /(\b)((\d+)|(\d+\.\d+))(-)/, '>>\5\1\2<<')) puts end end