# File lib/AWS/EC2/instances.rb, line 167
167:       def stop_instances( options = {} )
168:         options = { :instance_id => [] }.merge(options)
169:         raise ArgumentError, "No :instance_id provided" if options[:instance_id].nil? || options[:instance_id].empty?
170:         raise ArgumentError, ":force must be 'true' or 'false'" unless options[:force].nil? || [true, false].include?(options[:force])
171:         params = {}
172:         params.merge!(pathlist("InstanceId", options[:instance_id]))
173:         params["Force"] = options[:force].to_s unless options[:force].nil?
174:         return response_generator(:action => "StopInstances", :params => params)
175:       end