spotter

11-25-2005, 12:39 PM

There appears to be a quatization error of about 10 meters in easting when geodetic lat/lon is imported to Mappoint and displayed on a map. This error appears in areas where the absolute value of the longitude is greater than 100, i.e:

longitude = -122.098280, but NOT longitude = -74.009730.

I have noticed this at latitudes = 37.39428.

Steps to reproduce:

1) Create a latitude and longitude data series in Excel where each varies by 0.0001 degree steps. I used 100 steps.

2) Use the data import wizard to import this data to Mappoint.

There is a noticable stair step pattern in locations where there are three integer digits of longitude. The magnitude of the steps is approximately 10 meters, but only in easting, northing is unnaffected.

We would like to show better precision than this on our maps. Is there any way to overcome this limitation?

longitude = -122.098280, but NOT longitude = -74.009730.

I have noticed this at latitudes = 37.39428.

Steps to reproduce:

1) Create a latitude and longitude data series in Excel where each varies by 0.0001 degree steps. I used 100 steps.

2) Use the data import wizard to import this data to Mappoint.

There is a noticable stair step pattern in locations where there are three integer digits of longitude. The magnitude of the steps is approximately 10 meters, but only in easting, northing is unnaffected.

We would like to show better precision than this on our maps. Is there any way to overcome this limitation?