ArcPy – Convert Map Units from Feet to Decimal Degrees

arcpy

This is my problem:
I have an arcpy script that finds the XMax, XMin, YMax, and YMin of a polygon. It shows the results in feet, but I want them to be in decimal degrees.

In ArcMap I can change the data frame's display units to decimal degrees. But every time I run my script it shows the numbers in feet again.

Is there a solution for this in arcpy?

Best Answer

You can define a SearchCursor on the layer holding the polygon, and specify a spatial reference:

When specified, features will be projected on the fly using the spatial_reference provided.

See the help file under Setting a cursor's spatial reference for more info on setting up the search cursor with a new coordinate system. Once you've defined the cursor, you can find the projected extent using:

rows = arcpy.SearchCursor(featureclass,query,spatialReference)
row = rows.next()
polygon = row.shape
extent = polygon.extent

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ArcPy – Calculating XY Coordinates in Decimal Degrees from Projected Datasets

I think you can.

Just define the Spatial Reference in WGS-84 and use cursor using this Spatial Reference.

Coordinates are specified in the spatial_reference provided, and converted on the fly to the coordinate system of the dataset.

Fore more detail see this.

[GIS] Understanding use of extents in ArcPy

Found my answer, was just a confusion on my part. Obviously a lot of brain work and ArcGIS help was involved, so if someone cares to explain further what exactly I did, it may help to clarify things for others with the same confusions I had.

For those interested, here is the solution I came up with:

#Define Geodatabase and workspace
    #gdb = r"F:\...\####.gdb"
    env.workspace = gdb
    env.scratchworkspace = gdb
    # Set extent
    extent = arcpy.Extent(XMIN,YMIN,XMAX,YMAX)
#List available Feature Classes in a List
    def FCs_in_GDB(gdb):
        try:
            fcs = []
            for fds in arcpy.ListDatasets('','feature') + ['']:
                for fc in arcpy.ListFeatureClasses('','',fds):
                    fcs.append(os.path.join(fds, fc))
            return fcs
        except:
            print ("An Error has occured in FCs_in_GDB().")
    fc_list = FCs_in_GDB(gdb)
#Process Describe() filter on Count function
    for fc in fc_list:
        try:
            name = arcpy.Describe(fc).name
            x = arcpy.Describe(fc).extent
            overlaps = x.overlaps(extent)
            contains = x.contains(extent)
            within = x.within(extent)
            if overlaps==True or contains==True or within==True:
                count = arcpy.GetCount_management(fc)
        except:
            print ("An Error has occurred in fc_list().")

Best Answer

Related Solutions

ArcPy – Calculating XY Coordinates in Decimal Degrees from Projected Datasets

[GIS] Understanding use of extents in ArcPy

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