問題描述
我正在我的 Rails 應用程序視圖中顯示 Google 地圖，并將使用標記/覆蓋.
I'm displaying a Google map in my Rails app's view and will be using a marker/overlay.
坐標數據將來自手機 (GPS) 并存儲在我的 Rails 應用程序的數據庫中.
The coordinate data will be coming from a phone (GPS) and stored in my Rails app's db.
問題是，我不希望在我的網頁源中顯示精確的緯度/經度……也就是說，我想標記一個大概的位置，而不泄露真正的緯度/經度.
The problem is, I don't want the precise lat/long visible in the source of my web page ... i.e. I want to mark an approximate location without giving away the true lat/long.
如何舍入/截斷緯度/經度值，使它們仍然準確(例如，在一英里內)，但又不太準確?
How can I round/truncate the lat/long values so they are still accurate (say, within a mile)–but not too accurate?
(例如:你將如何舍入 35.2827524, -120.6596156 ?)
(Example: how would you round 35.2827524, -120.6596156 ?)
推薦答案
最簡單的做法是將兩個坐標四舍五入到一定的小數位，或者在坐標上添加隨機抖動:
The easiest thing to do would be either to round both coordinates to a certain number of decimal places, or add a random dither to the coordinates:
lat = Math.floor(lat*1000+0.5)/1000; (round within 0.001)
或
dither=0.001;
lat = lat + (Math.random()-0.5)*dither;
如果你真的想在一定的英里數內，你需要做更復雜的數學，可能使用極坐標.
If you really want to be within a certain number of miles, you'd need to do more-complex math, probably using polar coordinates.
這篇關于舍入經緯度以在 Google 地圖中顯示大致位置的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！