VERIFIED SOLUTION i

Resolve issue where the MapInfo Professional ObjectLen calculation varies when compared to length from data provider

MapInfo Professional®

Issue

Link length calculations in MapInfo Professional® might vary if a user compares his calculations with object length provided from data provider.   

Cause

ObjectLen(obj, "m") always calculates the object length spherical.

Resolution

UPDATED: September 7, 2017
If the data is using a Cartesian projection you will need to use Cartesian Functions such as:
  • CartesianArea( obj , str ) - Returns the area of the object as calculated in a flat, projected coordinate system using a Cartesian algorithm. The str value specifies an area unit name, such as "sq mi" or "sq km". Only regions, ellipses, rectangles, and rounded rectangles have any area.
  • CartesianPerimeter( obj , str ) - Returns the perimeter of the object as calculated in a flat, projected coordinate system using a Cartesian algorithm. The str value specifies a distance unit name, such as "mi" or "km". Only region, ellipse, and rectangle objects have non-zero perimeters.
  • CartesianDistance( num_x , num_y , num_x2 , num_y2 , str ) - Returns the distance between two locations as calculated in a flat, projected coordinate system using a Cartesian algorithm. The first two parameters specify the x and y value of the start location; the next two parameters specify the x and y value of the end location; the str parameter is a distance unit name, such as "mi" or "km".
  • CartesianObjectLen( obj , str ) - Returns the length of a line or polyline object as calculated in a flat, projected coordinate system using a Cartesian algorithm. The str value specifies a distance unit name such as "mi" or "km". Only line, polyline, and arc objects have non-zero lengths.