lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "ASF subversion and git services (JIRA)" <>
Subject [jira] [Commented] (LUCENE-7158) Haversin should use the earth's mean radius, not its max (equitorial)?
Date Fri, 01 Apr 2016 09:39:25 GMT


ASF subversion and git services commented on LUCENE-7158:

Commit cf7967cc467d9d697d520fcdf92fcdb52f7ddd4e in lucene-solr's branch refs/heads/master
from Mike McCandless
[;h=cf7967c ]

LUCENE-7158: use the same value (from WGS84) for earth's mean radius when we approximate it
as a sphere

> Haversin should use the earth's mean radius, not its max (equitorial)?
> ----------------------------------------------------------------------
>                 Key: LUCENE-7158
>                 URL:
>             Project: Lucene - Core
>          Issue Type: Improvement
>            Reporter: Michael McCandless
>         Attachments: LUCENE-7158.patch, LUCENE-7158.patch
> Across our spatial modules we seem to disagree about the earth's radius when we model
it as a sphere.
> I think in our haversin implementation we use equitorial (maximum) radius, but maybe
in spatial3d we use the earth's mean radius.
> I think mean makes more sense: the earth is actually a squashed sphere, so it's polar
radius is shorter than its equitorial radius.
> I think it's important, when we model the earth as a sphere, that we pick one radius
and try to use that one consistently?

This message was sent by Atlassian JIRA

To unsubscribe, e-mail:
For additional commands, e-mail:

View raw message