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Home - General / All posts - Topology Overlays, options

591 post(s)
#21-Jun-22 23:42

I'm working my way through the Topology Overlays bit of the manual and have just watched the video referenced Find Percentages of Open Space in ZIP Code Areas

The video shows an Options button that is no longer present in the current build. The options button, gave field options (sum, mean, etc) to pre set field conditions when running overlays. I understand the video shows the functions no longer present in the cutting edge builds.

Having searched the manual(s) I'm at a loss as to how to transfer fields mfd8 speak


7,025 post(s)
#22-Jun-22 06:06

That's an old video for a prior version, not the latest transform pane. See the user manual version of that example for how it's done using the latest version of the transform pane.


591 post(s)
#22-Jun-22 07:03

Thanks, that is perfect.

I'm really enjoying working my way through the examples.


972 post(s)
#24-Jun-22 18:08

the video show also that

- user can easely convert a SELECT ( viewing mode) into a CREATE table easely by addin in SQL a line INTO <tablename> !! in this case result tab is use !

-that manifold return "Cannot add record, rejected by index 'Name_x'." if table name inside INTO is alreday here in the project pane !! in this case log tab is use !

-that for select null content in cell we use IS NULL

at Computed Fields (

GeomAreaGeo([Geom], 6378137.01, 0.08181919084262149, 0) 

Returns the geodetic area of an area object in square meters. Returns NULL for lines and points. I think only some projection give exact result ( conserve area)


INFOGRAPHY union , LINK doc , API, deepl & keyboard shortcut


972 post(s)
#24-Jun-22 18:29

why the documentation say for return value for GeomArea <value> ?

- Does value mean all the column type like Floatx ( x=32,64 no float8 and no float16 !??) , INTy (y= 8,16,32,64) ?

- Can this <value> be store in a nvarchar column implicitly without use function CAST( )?

- What mean tolerance ( which unit? which range /scale ? ) if not set to zero ?

I ask this because when use C# code for extract text value from html page ; the convertion beetween " 23 45" ( all is node base in html ) to "2345" or 2345 is not easy and need code because API don't know howto interpret space !!


INFOGRAPHY union , LINK doc , API, deepl & keyboard shortcut

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