perform_search.rb

require 'riddle'
require 'riddle/0.9.9'

companies = %w(AmberBit Google HP)

client = Riddle::Client.new "localhost", 5000

client.match_mode = :extended
client.sort_mode = :extended
client.sort_by = "@geodist ASC"

puts "What's your latitude: "
lat = gets.to_f * Math::PI / 180.0

puts "What's your longitude: "
lng = gets.to_f * Math::PI / 180.0

puts "Top IT companies near you, ordered by distance: "

client.set_anchor "lat", lat, "lng", lng
client.query("", "pois")[:matches].each do |record|
  puts companies[record[:doc]-1]
end

pois.xml

<?xml version="1.0" encoding="utf-8"?>
<sphinx:docset>
  <sphinx:schema>
    <sphinx:field name="name"/>
    <sphinx:attr name="lat" type="float"/>
    <sphinx:attr name="lng" type="float"/>
  </sphinx:schema>

  <sphinx:document id="1">
    <name><![CDATA[AmberBit HQ]]></name>
    <lat>0.927042715037538</lat>
    <lng>0.403538937710426</lng>
  </sphinx:document>
  <sphinx:document id="2">
    <name><![CDATA[Google HQ]]></name>
    <lat>0.656188367092825</lat>
    <lng>-2.13395902872886</lng>
  </sphinx:document>
  <sphinx:document id="3">
    <name><![CDATA[Hewlett-Packard HQ]]></name>
    <lat>0.657782603191474</lat>
    <lng>-2.13395902872886</lng>
  </sphinx:document>
</sphinx:docset>

sphinx.conf

	source dummy
	{
	 type = xmlpipe2
	 xmlpipe_command = bash -c "cat pois.xml"
	}

	index pois
	{
	 source = dummy
	 path = tmp/places
	 docinfo = extern
	 mlock = 0
	 charset_type = utf-8
	 html_strip = 0
	}


	indexer
	{
	 mem_limit = 32M
	}

	searchd
	{
	 listen = 127.0.0.1:5000
	 log = tmp/searchd.log
	 query_log = tmp/query.log

	 read_timeout = 1
	 client_timeout = 1
	 max_children = 60
	 pid_file = tmp/searchd.pid
	 max_matches = 10000000
	 seamless_rotate = 1
	 preopen_indexes = 0
	 unlink_old = 1
	 mva_updates_pool = 1M
	 max_packet_size = 8M
	 max_filters = 256
	 max_filter_values = 4096
	}