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I am working to create a polygon from UTM coordinates. The script I am using fails with a "must be a sequence, not float" error:

Traceback (most recent call last):
  File "F:/sample/clipTiles.py", line 104, in <module>
    arcpy.Array([arcpy.Point(*coords) for coords in feature])))
TypeError: type object argument after * must be a sequence, not float

I have been working off the ArcGIS Polygon help section. My UTM coordinates are generated earlier in a script and take the following form:

[[734855.5142000001, 4744379.424500001], [740607.6685000001, 4744379.424500001], [740607.6685000001, 4736862.1753], [734855.5142000001, 4736862.1753]]

These are the min/max point pairs of a custom bounding box I need to convert to polygon.


                # feature_info eventually takes the following form: [[734855.5142000001, 4744379.424500001], [740607.6685000001, 4744379.424500001], [740607.6685000001, 4736862.1753], [734855.5142000001, 4736862.1753]]
                feature_info = [[xmin, ymax], [xmax,ymax], [xmax, ymin], [xmin, ymin]]

                # A list that will hold each of the Polygon objects
                features = []

                for feature in feature_info:
                    # Create a Polygon object based on the array of points
                    # Append to the list of Polygon objects
                    features.append(
                        arcpy.Polygon(
                            arcpy.Array([arcpy.Point(*coords) for coords in feature])))

                # Persist a copy of the Polyline objects using CopyFeatures
                outshp = os.path.join(outws, row[2] + "_shp")
                arcpy.CopyFeatures_management(features, outshp)

How can I write these UTM coordinates to a polygon featureclass?

3

I do it this way by creating an Array of Point objects that form a line that closes back on itself, and then creating a Polygon object from that Array:

# feature_info eventually takes the following form: [[734855.5142000001, 4744379.424500001], [740607.6685000001, 4744379.424500001], [740607.6685000001, 4736862.1753], [734855.5142000001, 4736862.1753]]
feature_info = [(xmin, ymax), (xmax,ymax), (xmax, ymin), (xmin, ymin)]

lineArray = arcpy.Array()

for x,y in feature_info:
    lineArray.add(arcpy.Point(x,y))
lineArray.add(lineArray.getObject(0))
polygon = arcpy.Polygon(lineArray)

# Persist a copy of the Polyline objects using CopyFeatures
outshp = os.path.join(outws, row[2] + "_shp")
arcpy.CopyFeatures_management(polygon, outshp)

I suspect that lists and tuples can be used interchangeably in my first line so try:

feature_info = [[xmin, ymax], [xmax,ymax], [xmax, ymin], [xmin, ymin]]

If it complains about requiring a tuple then create a new empty list and append into it by iterating your list of lists, using the tuple function to "freeze" each one, into a list of tuples.

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