You may need to set a Bounds clause to get the resolution you want.

A 2^31*2^31 virtual grid underlies any Mapinfo coordinate system. 
Actual coordinate values from the minimum bounds and points at each
integer step along the grid.  

So even if you create points with integer coordinates in the real world, 
you'll get funny coordinates if the points in the underlying virtual grid
don't fall precisely on integer values.

To get the results you want, you need to pick a minimum spatial granularity
first and derive bounds from there.  The granularity needs to be a rational
number that is an exact divisor of 1.  A power of 10 is best.   Multiply
the granularity you pick by 2^31-1 (2147483647) and this is the difference
between the minimum bounds and maximum bounds.  Then, choose a minimum
bounds X and Y convenient to your project and add the previous result to
each to get the maximum X and Y.

So, you could use a granularity of 0.01 (i.e. 1 cm) and have a bounds clause


Bounds 0, 0, 2147483.47, 2147483.47

Or, you could use a granularity of 1 and have a bounds clause of

Bounds -100000000,-1000000000, 1147483647, 1147483647

Also, when you're setting the "current coordinate system" in the MapBasic
window or a MapBasic application, 

remember to use

Set Coordsys Table xxxxxx

instead of

Set Coordsys Earth ....

in order to use the bounds clause for CreatePoint and Create Object and
things like that.


Hope this helps
Spencer

 

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] 
Sent: Monday, February 28, 2005 8:46 AM
To: [email protected]
Subject: MI-L shift in coordinates

hi there 

Is there anybody having same problem.

I have a table in UTM ED 50 center meridian 33 degree
map window projection is also same

I create object reading coordinates from database.
numbers are integer like 525000 x and 4032000 y
I create object as variable and add nodes one by one

when I insert object into table
corner points returns as 
524,999.9985  x coordinate 
4,032,000.005 y coordinate


what can be the problem?




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