redis自3.2版本开始新增对geo(地理位置)的支持，但是地球不是一个完美的球体，在最坏的情况下的偏差可能是0.5%。接近两极的区域是不支持的，支持坐标的有效的经度从-180度到180度；有效的纬度从-85.05112878度到85.05112878度，超出范围将会报错。
我喜欢爬山，学习GEO的时候我也以山的坐标做演示，我的坐标是：
116.517159,39.922267
我整理了一些山的坐标
$mountainCoordinates = array(
array('115.793844', '40.584459', 'Hai_tuo'),//海陀山坐标
array('115.056232', '39.948933', 'Small_wutai'),//小五台山坐标
array('114.173822', '27.474563', 'Wu_gong'),//武功山坐标
array('111.341648', '25.518178', 'Leek_ridge'),//韭菜岭坐标
array('103.901761', '31.60487', 'Jiu_ding'),//九顶山坐标
array('107.398009', '34.057777', 'Ao_Shan'),//鳌山坐标
);1.向mountainCoordinates的key里增加坐标
try {
$redis = new Redis();
$redis->connect('192.168.75.132', 6379);
foreach ($mountainCoordinates as $coordinates){
$param = array('geoadd', 'mountainCoordinates');
$param = array_merge($param, $coordinates);
$ret = call_user_func_array(array($redis, 'rawCommand'), $param);
print_r($ret);
}
} catch (Exception $e){
echo $e->getMessage();
}执行结果
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int(1) int(1) int(1) int(1) int(1) int(1)
2.获取坐标
try {
$redis = new Redis();
$redis->connect('192.168.75.132', 6379);
$param = array('geopos', 'mountainCoordinates', 'Hai_tuo', 'Wu_gong', 'Jiu_ding');
$ret = call_user_func_array(array($redis, 'rawCommand'), $param);
print_r($ret);
} catch (Exception $e){
echo $e->getMessage();
}执行结果
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Array
(
[0] => Array
(
[0] => 115.79384654760360718
[1] => 40.58445845049069334
)
[1] => Array
(
[0] => 114.1738244891166687
[1] => 27.47456377424472151
)
[2] => Array
(
[0] => 103.90176326036453247
[1] => 31.60486909089710394
)
)3.计算两个坐标间距离
try {
$redis = new Redis();
$redis->connect('192.168.75.132', 6379);
$param = array('geodist', 'mountainCoordinates', 'Hai_tuo', 'Small_wutai', 'km');
$ret = call_user_func_array(array($redis, 'rawCommand'), $param);
var_dump($ret);
} catch (Exception $e){
echo $e->getMessage();
}执行结果：海陀山和小五台山之间距离是94.4219km
string(7) "94.4219"
4.以我的坐标为原点，按半径100km取坐标（找出离我100公里以内的山）
try {
$redis = new Redis();
$redis->connect('192.168.75.132', 6379);
$param = array('georadius', 'mountainCoordinates', '116.517159', '39.922267', '100', 'km', 'WITHDIST', 'WITHCOORD');
$ret = call_user_func_array(array($redis, 'rawCommand'), $param);
print_r($ret);
} catch (Exception $e){
echo $e->getMessage();
}执行结果：只有海陀山，离我95.8884km
Array
(
[0] => Array
(
[0] => Hai_tuo
[1] => 95.8884
[2] => Array
(
[0] => 115.79384654760360718
[1] => 40.58445845049069334
)
)
)5.以我的坐标为原点，按半径1500km取坐标（找出离我1500公里以内的山）
try {
$redis = new Redis();
$redis->connect('192.168.75.132', 6379);
$param = array('georadius', 'mountainCoordinates', '116.517159', '39.922267', '1500', 'km', 'WITHDIST', 'WITHCOORD');
$ret = call_user_func_array(array($redis, 'rawCommand'), $param);
print_r($ret);
} catch (Exception $e){
echo $e->getMessage();
}执行结果：找出了5座山
Array
(
[0] => Array
(
[0] => Jiu_ding
[1] => 1464.4350
[2] => Array
(
[0] => 103.90176326036453247
[1] => 31.60486909089710394
)
)
[1] => Array
(
[0] => Ao_Shan
[1] => 1039.1217
[2] => Array
(
[0] => 107.3980066180229187
[1] => 34.05777705537607147
)
)
[2] => Array
(
[0] => Wu_gong
[1] => 1401.2353
[2] => Array
(
[0] => 114.1738244891166687
[1] => 27.47456377424472151
)
)
[3] => Array
(
[0] => Small_wutai
[1] => 124124.6283
[2] => Array
(
[0] => 115.05623370409011841
[1] => 39.94893288365195616
)
)
[4] => Array
(
[0] => Hai_tuo
[1] => 95.8884
[2] => Array
(
[0] => 115.79384654760360718
[1] => 40.58445845049069334
)
)
)6.以小五台山的坐标为原点，按半径1000km取坐标（找出离小五台山1000公里以内的山）
try {
$redis = new Redis();
$redis->connect('192.168.75.132', 6379);
$param = array('georadiusbymember', 'mountainCoordinates', 'Small_wutai', '1000', 'km', 'WITHDIST', 'WITHCOORD');
$ret = call_user_func_array(array($redis, 'rawCommand'), $param);
print_r($ret);
} catch (Exception $e){
echo $e->getMessage();
}执行结果：排除小五台自己，找到了鳌山和海陀山
Array
(
[0] => Array
(
[0] => Small_wutai
[1] => 0.0000
[2] => Array
(
[0] => 115.05623370409011841
[1] => 39.94893288365195616
)
)
[1] => Array
(
[0] => Hai_tuo
[1] => 94.4219
[2] => Array
(
[0] => 115.79384654760360718
[1] => 40.58445845049069334
)
)
[2] => Array
(
[0] => Ao_Shan
[1] => 943.7873
[2] => Array
(
[0] => 107.3980066180229187
[1] => 34.05777705537607147
)
)
) 
