I have been making comparisons of the area of various objects, and have
found MapInfo's area calculating function to be seriously broken, at least
in some projections (Polar Azimuthal projections).
Attached is the MB code and an MBX (both are tiny) which demonstrates the
problem. To summarise what the programme does:
1/ it draws two triangles of equal size,
2/ labels the triangles with their area, and
3/ displays the area in a browser.
First problem: the labels don't show on the map because of an apparent bug
in the label positioning function. You have to zoom out or pan up to see
where the labels have gone.
Second problem is the areas: one area calculated as 2,375,776 sq km, the
other area as 5,688 sq km. Three orders of magnitude difference.
I suspect the problem is related to projection. If anyone knows what is
happening here, could you please let me know? What projections are "safe"
and which are "broken"?
Cheers
Mark O.
<<area_bug.MB>> <<area_bug.MBX>>
begin 600 area_bug.MB
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end
begin 600 area_bug.MBX
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`
end
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