Sqlalchemy: Latitude and Longitude Float Precision?

发布于 2011-07-07 00:32:08

I'm using Sqlalchemy to define my tables and such and here is some code I came up with:

locations = Table('locations', Base.metadata,
Column("lat", Float(Precision=64), primary_key=True),
Column("lng", Float(Precision=64), primary_key=True),
)

I read somewhere that latitude and longitude require better precision than floats, usually double precision. So I set the precision manually to 64, is this sufficient? Overkill? Would this even help for my situation?

Questioner

john

Viewed

Original

masebase 2015-12-20 11:29:38

It depends on what you are using your data for. If you use a float it will be ok if the you only need it down to about the meter level of detail. Using the data in graphically applications will cause a jitter effect if the user zooms in to far. For more about jitter and see Precisions, Precisions. Hope this helps.

热门github

Implementation of paper - YOLOv9: Learning What You Want to Learn Using Programmable Gradient Information

A Windows and Office activator using HWID / Ohook / KMS38 / Online KMS activation methods, with a focus on open-source code and fewer antivirus detections.

Get up and running with Llama 2, Mistral, Gemma, and other large language models.

该项目可以让你通过订阅的方式使用Cloudflare WARP+，自动获取流量。This project enables you to use Cloudflare WARP+ through subscription, automatically acquiring traffic.

Multi functional app to find duplicates, empty folders, similar images etc.

Xray panel supporting multi-protocol multi-user expire day & traffic & ip limit (Vmess & Vless & Trojan & ShadowSocks & Wireguard)

The Free Software Media System

lightweight, standalone C++ inference engine for Google's Gemma models.

📚 Freely available programming books

A collective list of free APIs

1️⃣🐝🏎️ The One Billion Row Challenge -- A fun exploration of how quickly 1B rows from a text file can be aggregated with Java

🎓 Path to a free self-taught education in Computer Science!

Curso para aprender el lenguaje de programación Python desde cero y para principiantes. 75 clases, 37 horas en vídeo, código, proyectos y grupo de chat. Fundamentos, frontend, backend, testing, IA...

This repository contains System Design resources which are useful while preparing for interviews and learning Distributed Systems

Mamba is a new state space model architecture showing promising performance on information-dense data such as language modeling, where previous subquadratic models fall short of Transformers. It is based on the line of progress on structured state space models, with an efficient hardware-aware design and implementation in the spirit of FlashAttention.

Sqlalchemy: Latitude and Longitude Float Precision?

热门帖子

热门github