[postgis-devel] about lwcurve in postgis

[xie jiong]

SQL-MM specification's curve is the base class of circluar string and line string,
so use curve as circle isn't very proper i think.

----- Original Message ----- 
From: "Mark Leslie" <mrk.leslie at gmail.com>
To: "PostGIS Development Discussion" <postgis-devel at postgis.refractions.net>
Sent: Thursday, June 19, 2008 7:40 AM
Subject: Re: [postgis-devel] about lwcurve in postgis


> 2008/6/18 xie jiong <xie_jiong at 163.com>:
>>
>> HI:
>>
>> in current postgis, lwcurve only represent circularstring, so why use
>> curve name?
>>
>> Jiong
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>> postgis-devel at postgis.refractions.net
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>>
>>
> 
> One answer is that a circle is a curve.
> 
> The correct answer is that the curved geometry support was developed
> to the SQL-MM specification, which supports only the circular string
> version of curves, so our naming convension is directly derived from
> theirs.
> 
> -- 
> Mark Leslie
> Geospatial Software Architect
> LISAsoft
> http://www.lisasoft.com/LISAsoft/SupportedProducts.html
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