Subject: [Geojson] Why geojson use X,Y format?

From: Mohammed Zia <[email-masked]>
Date: Fri, 6 May 2016 23:29:47 +0300

Hello All,

My Q is very simple and direct. Unlike leaflet mapping lib, google maps,
and even ISO specifications of displaying coordinates in *Lat Long format*,
why does Geojson use *Long Lat format* for point representation? Kindly
give a bit insight about pros and cons.

Thanks beforehand.

-- 
*Zia, Mohammed*
GeoSpatial FOSS4G Developer and Doctoral Student,
Istanbul Technical University, Turkey.
*Phone*: 90 507 030 2907
*LinkedIn <https://tr.linkedin.com/pub/mohammed-zia/61/2b4/809> , **Twitter*:
__ZIA_
*Careers@StackOverflow <http://careers.stackoverflow.com/zia>*
*Demo-maps <http://maps.itu.edu.tr/> , Blog
<https://ziamohammmed.wordpress.com/>*

---

From: James Winterbottom <[email-masked]>
Date: Sat, 7 May 2016 21:34:15 +1000

Long, Lat is actual how geospatial systems operate on data.
If you play with Geospatial databases the format is always long, lat.
If you think about cartesian coordinates, X represents longitude and Y represent latitude.

Cheers
James

> On 7 May 2016, at 6:29 am, Mohammed Zia <[email-masked]> wrote:
> 
> Hello All,
> 
> My Q is very simple and direct. Unlike leaflet mapping lib, google maps, and even ISO specifications of displaying coordinates in Lat Long format, why does Geojson use Long Lat format for point representation? Kindly give a bit insight about pros and cons.
> 
> Thanks beforehand.
> 
> -- 
> Zia, Mohammed
> Phone: 90 507 030 2907
> LinkedIn <https://tr.linkedin.com/pub/mohammed-zia/61/2b4/809> , Twitter: __ZIA_ 
> Careers@StackOverflow <http://careers.stackoverflow.com/zia>
> Demo-maps <http://maps.itu.edu.tr/> , Blog <https://ziamohammmed.wordpress.com/>
> 
> 
> _______________________________________________
> GeoJSON mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/geojson

---

From: Carl Reed <[email-masked]>
Date: Sat, 7 May 2016 09:28:58 -0600

James -

I beg to differ.

The following is my personal view.

I have worked geospatial technology for over 40 years. I worked with
geodetic (spherical) coordinate systems back in the late 1970's. The early
GIS and mapping systems that took a earth centric view of the world (and
not that the earth is flat) followed photogrammetry and geodesy best
practice - coordinate order for WGS 72 and now WGS 84 was (and still is)
Lat/Long. Data stores were Lat/Long - not Long/Lat. Today, spatial database
stores such as Oracle Spatial store WGS coordinates as Lat/Long. This is
true for the majority of spatial databases. GPS is Lat/Long. The majority
of standards that deal with geodetic coordinates use Lat/Long coordinate
order. The military, the oil industry, aviation, and so on all use Lat/Long
coordinate order. In the 1980s and 1990s I worked designing and
implementing numerous geospatial systems - all Lat/Long.

Fast forward to today. While most systems work in Lat/Long, there is a
significant number of encodings and systems that work in Long/Lat. My
theory is that the use of Long/Lat today is the result of a number of
factors, such as perceived ease of programming. Having KML as Long/Lat
definitely had an impact. Geography GIS programs not teaching students
about coordinate reference systems is another.

So now we live in a bit more of a mixed environment. The key to
interoperability is that the software, encoding, programmer, and/or
documentation "tell the truth" about the coordinate order of the data being
delivered.This is why CRS specifications and definitions are so important
in standard work. And why they can be so contentious! Anyway, SQL/MM, OGC
Simple Features, and the databases that implement these standards specify
storing geodetic coordinates based on the CRS definitions as stored in the
EPSG database or some other normative reference for CRS parameters. EPSG
4326 specifies an axis order of Lat/Long. There are other EPSG definitions
that specify Long/Lat. I think the operative design concept today is pick
the axis order that best suits the target audience for your spec or system
and then properly advertise that decision.

Back to coffee.

Regards

Carl

On Sat, May 7, 2016 at 5:34 AM, James Winterbottom <
[email-masked]> wrote:

> *LinkedIn <https://tr.linkedin.com/pub/mohammed-zia/61/2b4/809> , *
> *Twitter*: __ZIA_

-- 
Carl Reed, PhD
Carl Reed and Associates

Mobile: 970-402-0284

---

From: James Winterbottom <[email-masked]>
Date: Sun, 8 May 2016 04:06:36 +1000

That works for me

Sent from my iPhone

> On 8 May 2016, at 1:28 am, Carl Reed <[email-masked]> wrote:
> 
> James -
> 
> I beg to differ.
> 
> I have worked geospatial technology for over 40 years. I worked with geodetic (spherical) coordinate systems back in the late 1970's. The early GIS and mapping systems that took a earth centric view of the world (and not that the earth is flat) followed photogrammetry and geodesy best practice - coordinate order for WGS 72 and now WGS 84 was (and still is) Lat/Long. Data stores were Lat/Long - not Long/Lat. Today, spatial database stores such as Oracle Spatial store WGS coordinates as Lat/Long. This is true for the majority of spatial databases. GPS is Lat/Long. The majority of standards that deal with geodetic coordinates use Lat/Long coordinate order. The military, the oil industry, aviation, and so on all use Lat/Long coordinate order. In the 1980s and 1990s I worked designing and implementing numerous geospatial systems - all Lat/Long.
> 
> Fast forward to today. While most systems work in Lat/Long, there is a significant number of encodings and systems that work in Long/Lat. My theory is that the use of Long/Lat today is the result of a number of factors, such as perceived ease of programming. Having KML as Long/Lat definitely had an impact. Geography GIS programs not teaching students about coordinate reference systems is another.
> 
> So now we live in a bit more of a mixed environment. The key to interoperability is that the software, encoding, programmer, and/or documentation "tell the truth" about the coordinate order of the data being delivered.This is why CRS specifications and definitions are so important in standard work. And why they can be so contentious! Anyway, SQL/MM, OGC Simple Features, and the databases that implement these standards specify storing geodetic coordinates based on the CRS definitions as stored in the EPSG database or some other normative reference for CRS parameters. EPSG 4326 specifies an axis order of Lat/Long. There are other EPSG definitions that specify Long/Lat. I think the operative design concept today is pick the axis order that best suits the target audience for your spec or system and then properly advertise that decision.
> 
> Back to coffee.
> 
> Regards
> 
> Carl
> 
> 
> 
> 
>> On Sat, May 7, 2016 at 5:34 AM, James Winterbottom <[email-masked]> wrote:
>>> LinkedIn , Twitter: __ZIA_ 
>>> Careers@StackOverflow
>>> Demo-maps , Blog
>>> 
>>>

---

From: Calvin Metcalf <[email-masked]>
Date: Sun, 08 May 2016 13:00:12 +0000

Overview of who does what http://www.macwright.org/lonlat/

On Sat, May 7, 2016, 2:06 PM James Winterbottom <
[email-masked]> wrote:

>> and even ISO specifications of displaying coordinates in *Lat Long
>> format*, why does Geojson use *Long Lat format* for point
>> representation? Kindly give a bit insight about pros and cons.
>>
>> Thanks beforehand.
>>
>> --
>> *Zia, Mohammed*

---

From: Carl Reed <[email-masked]>
Date: Sun, 8 May 2016 08:26:21 -0600

Calvin -

Thanks for the info.

I would add many standards that have a "geo" or location element (or
elements) specify lat/lon order. Note that these are not OGC standards :-)

IETF iCalendar
OASIS CAP (Common Alert Protocol)
IETF DHCP
IETF PIDF-LO
IETF geo uri
OASIS EDXL-DE
W3C Geo vocabulary

What software does with the location information is another matter.

I could go on with generating a list but I am watching the Giro de Italia
:-) Chad Haga, who used to ride for a local Fort Collins team, is currently
in 11th place.

Regards

Carl

-- 
Carl Reed, PhD
Carl Reed and Associates

Mobile: 970-402-0284

---

From: Calvin Metcalf <[email-masked]>
Date: Sun, 08 May 2016 14:44:47 +0000

Not by me, feel free to open a pull though https://github.com/tmcw/lonlat

On Sun, May 8, 2016, 10:26 AM Carl Reed <[email-masked]> wrote:

>>>> My Q is very simple and direct. Unlike leaflet mapping lib, google
>>>> maps, and even ISO specifications of displaying coordinates in *Lat
>>>> Long format*, why does Geojson use *Long Lat format* for point