# I am the Watcher. I am your guide through this vast new twtiverse.
# 
# Usage:
#     https://watcher.sour.is/api/plain/users              View list of users and latest twt date.
#     https://watcher.sour.is/api/plain/twt                View all twts.
#     https://watcher.sour.is/api/plain/mentions?uri=:uri  View all mentions for uri.
#     https://watcher.sour.is/api/plain/conv/:hash         View all twts for a conversation subject.
# 
# Options:
#     uri     Filter to show a specific users twts.
#     offset  Start index for quey.
#     limit   Count of items to return (going back in time).
# 
# twt range = 1 1
# self = https://watcher.sour.is/conv/wquqepa
滴滴打車如何找出方圓一千米內的乘客?揭開 GeoHash 的神祕面紗**
背景--不知道大家是否思考過一個問題,在一些場景下(如大家在使用高德地圖打車的時候,鄰近的司機是如何知道你在他的附近並將你的打車通知推送給他去接單的?)是如何實現的?一般來講,大家也許會想到,首先肯定需要知道每位乘客的經緯度 (lng,lat),也即是二維座標(當然這是在絕對理想的情況,不考慮上下坡度)。而在知道了經緯度之後,一個暴力簡單且容易想到的思路就是將經緯度這個「二元組」 都存放在一個「 ⌘ Read more