looking for a python transform

Question

is there a python equivalent to the ITransform2D.Move method?
i am trying to move a polygon from one place to another based on a known XY coordinate
something like:

!Shape.centroid.x! = new_coordx
!Shape.centroid.x! = new_coordy
move

AdarshMadhavan · Answer

Seems to be working.

However , If the file to be processed is non-georeferenced, will this work ?

LoganPugh · Answer

Here's a function you can try within an UpdateCursor. Set the shape of the row to the return value of this function and call updateRow. Written for arcgisscripting so it should work with both 9.3 and 10.def moveGeomToPoint(geometry, x, y):
    """Returns a geometry whose coordinates are shifted such that the new centroid is located at the coordinates x and y"""
    # Get the current centroid
    oldCentroid = geometry.TrueCentroid

# Get the delta x and y factors
    dX = x - oldCentroid.x
    dY = y - oldCentroid.y

# Print details of translation
    print "Current Centroid: (%.12F, %.12F)" % (oldCentroid.x, oldCentroid.y)
    print "New Centroid: (%.12F, %.12F)" % (x, y)
    print "dX, dY: (%.12F, %.12F)" % (dX, dY)

# Check if geometry is point first
    if geometry.type == "point":
        # Get the existing point object
        pnt = geometry.GetPart()

# Create a new point object and assign to it the new translated coordinates
        newPnt = gp.CreateObject("Point")
        newPnt.x = pnt.x + dX
        newPnt.y = pnt.y + dY

# Return the new point instead of going through all the parts
        return newPnt

# Keep track of where we are in the geometry array
    partnum = 0
    partcount = geometry.PartCount

# Create a new geometry array -- this is what we are ultimately going to return
    newGeom = gp.CreateObject("Array")

# Loop through all of the parts in the geometry array
    while partnum < partcount:
        print "Part " + str(partnum) + ":"
        part = geometry.GetPart(partnum)

# Create a new array just for the part we are currently on
        newPart = gp.CreateObject("Array")

# Get the first vertex of the current part
        pnt = part.Next()
        pntcount = 0

# Enter while loop for each vertex
        while pnt:
            # Print x,y coordinates of current point and new point
            oldX = pnt.x
            oldY = pnt.y
            newX = oldX + dX
            newY = oldY + dY
            print "%.12F, %.12F --> %.12F, %.12F" % (oldX, oldY, newX, newY)

# Create a new point object and assign to it the new translated coordinates
            newPnt = gp.CreateObject("Point")
            newPnt.x = newX
            newPnt.y = newY

# Add the new point object to the new part array
            newPart.add(newPnt)

pnt = part.Next()
            pntcount += 1

# If pnt is null, either the part is finished or there is an interior ring
            if not pnt:
                pnt = part.Next()
                if pnt:
                    print "Interior Ring:"
        # Add the new part to the new geometry array
        newGeom.add(newPart)
        partnum += 1
    return newGeom

Example usage:import arcgisscripting
global gp
gp = arcgisscripting.create(9.3)
fc = "c:/temp/geomTest3.shp"
rows = gp.UpdateCursor(fc)
row = rows.Next()
while row:
    row.shape = moveGeomToPoint(row.shape, 8, -8)
    rows.updateRow(row)
    row = rows.Next()
del row
del rows

ChrisSnyder · Answer

How about building a custom spatial reference that is the same as your standard one but just with different FalseEasting and FalseNorthing values?

Then you could use this custom SR in a cursor (or just the project command for that matter)...