topic Re: Spatially Enabled Dataframe in ArcGIS API for Python Questions

Spatially Enabled Dataframe

OisinSlevin — Wed, 16 Jan 2019 16:39:53 GMT

Hi Guys,
Having an issue with a projection where the projection is off by 70 meters

example:

gis = GIS("url", "user", password)
content=gis.content.get("ID")

layers=content.layers

points=pd.DataFrame.spatial.from_layer(layers[0])

points['SHAPE']=points['SHAPE'].geom.project_as(29900)

my source data is in EPSG:2157 but i need EPSG:29900, when I view the source data in an eternal package it aligns with the the backround map,

if I project to EPSG:29900 I'm roughly 70meters off from the basemap

if i project_as EPSG:4326 it seems to work with no issues and aligns with the base map.

Is there any known issues or any other ways to changing coordinate systems.

have had the same issue using spatial DataFrame and Spatially Enabled Dataframe.
I've also used geopandas to convert the data and that works perfectly so I'm nearly certain there is an issue.

Re: Spatially Enabled Dataframe

JoshuaBixby — Wed, 16 Jan 2019 19:08:33 GMT

Is it just between EPSG:2157 and EPSG:29900 or can you reproduce between other combinations? Also, what if you try from EPSG:2157 to EPSG:29902 ? According to several sites, EPSG:29900 is deprecated, so maybe that is causing an issue with the transformation.

Re: Spatially Enabled Dataframe

OisinSlevin — Thu, 17 Jan 2019 10:45:18 GMT

I've tried using 29902, I've also tried converting from 2157 to 4326, and then projecting to 29902, so I think its just an issue with the projection to 29902.

Re: Spatially Enabled Dataframe

simoxu — Sun, 12 Dec 2021 09:47:58 GMT

I suspect the projection was done as expected.

Could you try this:

gis = GIS("url", "user", password)
content=gis.content.get("ID") 

layers=content.layers


#points=pd.DataFrame.spatial.from_layer(layers[0])
#points['SHAPE']=points['SHAPE'].geom.project_as(29900)

feature_layer = layers[0]
fset = feature_layer.query(out_sr=29900)
sdf1 = fset.sdf

# then you can export the sdf1 as other formats if you like‍‍‍‍‍‍‍‍‍‍‍‍‍‍

The difference is the projection will be done on the server rather than in the browser, at least this is what I am guessing

Re: Spatially Enabled Dataframe

OisinSlevin — Fri, 18 Jan 2019 10:51:15 GMT

Thanks this fixes my issue, although I'm still concerned if projections don't match ?