Many thanks to the following for their suggestions to my request (see below). Bill Thoen, Uffe Kousgaard, Mircea Baila, Patrick Palmier, and Jennifer McQuiston.
The most efficient solution proposed was to create circles from the points and then do the intersection query, then turn the circles back into points. Changing the obj to a buffer also worked well. (as opposed to creating a buffer around the point) When creating buffers around the points, (or the lines) the table is appended with the buffers but they do not have any attributes and the resulting browser has no information in the columns. Buffering is also slower than creating circles, especially for lines. I will now consider creating a .mbx tool that will facilitate "point on line" type queries. Thanks very much for your assistance. Cheers Steve Ware >>> "Stephen Ware" <[EMAIL PROTECTED]> 29/01/2002 15:03:20 >>> Points near lines: I need to be able to select points that intersect lines having specific attributes. For example Select Accidents that happened on Category 4 Roads. The points are very close to, but not exactly on the lines and therefore the "intersection" operator does not select any records. I have tried to buffer the individual points with a small buffer (1 mm) and this selects the records but as the buffers do not hold any attributes of the points the results are not very useful. Can anyone suggest a way to do one or more of the following: 1. Make the points snap to the nearest line without editing the line, I do not want to mess up my base file with new points. This should make the "Intersection" operator produce results. 2. Get the point buffers to acquire the attributes of the points. Then I would have a browser list of the accident details of the selected points. 3. Convert the points into regions of about 0.5 mm diameter, then intersection with the lines would be guaranteed. 4. Using MapBasic, calculate the x and y Cartesian coordinates of a point a given distance from the start of the line such that it falls exactly on the line but is not a node of that line. This is how the accidents are geocoded now but I can't seem to hit the line exactly. Is it something to do with precision? Thanks for any suggestions. Steve Ware Dept. of Infrastructure, Energy, and Resources Roads and Public Transport Division Tasmania, Australia _______________________________________________________________________ List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, send e-mail to [EMAIL PROTECTED] and put "unsubscribe MapInfo-L" in the message body. _______________________________________________________________________ List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, send e-mail to [EMAIL PROTECTED] and put "unsubscribe MapInfo-L" in the message body.
