Why am I getting “sequence size must match size of the row” error?

Question

I'm trying to use an Insert Cursor to insert a point geometry into an existing point feature class.

I'm finding the coordinate and appending them to a list called rowValues, ex:

rowValues.append("((({0}, {1}), 34))".format(X, Y))

This is giving me a list of value in this format:

((3656320.51246, 1613747.99484), 34)

Here is the cursor I am using:

cursor = arcpy.da.InsertCursor("Points",("SHAPE@XY","QuarterSections"))

When I run this code:

for row in cursor:
    cursor.insertRow(row)

I get this follow error:

Traceback (most recent call last):
  File "Quarter.py", line 110, in <module>
    cursor.insertRow(row)
TypeError: sequence size must match size of the row

Can I not use the string formatting? I've been trying to figure this out for awhile now, but I'm stumped.

Answer 1

The cursor is expecting a tuple, not a string. You might be able to convert the string to a tuple after the fact using ast.literal_eval() as described in this answer. However, it would be far better practice to produce the tuple without using a string as an intermediary.

The better way to do this would be to change:

"((({0}, {1}), 34))".format(X, Y)

To:

((X, Y), 34)

Is there a particular reason you are using a string?