# File lib_wpm/wpm.rb, line 722
    def check_float(string)
      case (string.strip)
      when /^[+-]?\d+(\.\d+)?$/, /^[+-]?\.\d+$/
        return
      when /^[+-]?\d+(\.\d+)?[Ee][+-]?\d+$/, /^[+-]?\.\d+[Ee][+-]?\d+$/
        return
      else
        raise "not a float: #{string.inspect}"
      end
    end