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I have a table of point, with a bunch of data attached. I need to replace them with polygons.

Drawing a polygon creates a new record. Deleting the point deletes the record.

How can I replace the point with a polygon without creating a new record and copy and pasting the data over?

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If each point has a unique id - then you buffer your points creates a polygon, join tables from original points to polygons –  Mapperz Feb 23 '12 at 17:35

2 Answers 2

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You are talking about digitising new objects, so I have assumed that the replacement polygons for each existing point don't already exist in another table that can be joined, nor can they be derived from the existing point object by an operation such as a buffer.

In MapInfo, make the layer that contains the objects to be replaced editable in a map window, then select one or more of them and choose Edit > Clear Map Objects Only. This will delete only the object, retaining the attribute record. Now to digitise a new object associated with this record, select the record from the browser window and digitise an object as you would normally. On completion of the digitising, the new object will be associated with the existing attribute record rather than a new empty record.

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That's what I was looking for! Thanks. –  Mr_Chimp Feb 24 '12 at 15:50
    
My apolgies, didn't realize you were using mapInfo and not ArcGIS. –  Tim Feb 24 '12 at 18:18

Does your table include spatial data for each point? What kind of shape of polygon and what size are you looking for. If your table has spatial data, geocode the locations. This will output a point feature class, with the original attribute data from your table attached. You could then use the buffer geoprcessing tool to create circular polygons around each point at a specified distance (i.e. miles). The output is a polygon feature class, still with the original attribute data preserved.

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Yes the points are currently mapped. The polygons aren't any regular size, they are fields, buildings etc. The points were place holders to show the rough locations. Data was then input against these. Now that I know the exact site boundaries I want to replace the points. –  Mr_Chimp Feb 23 '12 at 16:40
    
Ok so you have a polygon layer with no attributes, and a point layer with all of the attributes. You want the points attributes attached to the polygon layer. Is this correct? Does each point intersect only ONE polygon? –  Tim Feb 23 '12 at 16:49
    
No, I only have a point layer with attributes. The polygons are only on paper at the moment. –  Mr_Chimp Feb 23 '12 at 16:53
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I see, so you'll have to digitize each of the polygons eventually. So this is what i would suggest, create a new feature class and digitize each of your polygons. Instead of copying all of your data from the points one by one, create a field in the polygon feature class called Reference_ID or dsomething to that effect. After you draw each polygon add the corresponding points OID or FID (a unique key). Then when you are finished digitizing join the point layer to your polygon layer based on that common ID (Reference_ID = OID/FID) then export it as a FC or shapefile. –  Tim Feb 23 '12 at 17:04
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Another way is by using a spatial join if you don't want to input any data into the polygons as you draw them. You'd have to make sure that each polygon is drawn on top of each point, one point per poly, and then when finished drawing, join the point layer to the polygon layer based on spatial location. Right click polygon layer > join > select "join data based on spatial location" from drop down > select "each poly will be given the attributes of the points closest to its boundary". The export will be a polygon layer with the point attributes, you'll prob have to delete some fields though. –  Tim Feb 23 '12 at 17:06

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