Hello everyone, I received some good replies. I'm not sure if people want their names published since they sent the replies directly to me but I am very thankful to them!
1) You can use an SQL query: >From tables: Layer1, Layer2 Columns: proportionoverlap(Layer1.obj, Layer2.obj) Here's more on the ProportionOverlap function: Purpose: Returns a number that indicates what percentage of one object is covered by another object. Syntax: ProportionOverlap(object1,object2) object1 is the bottom object (not text or points) object2 is the top object (not text or points) Return Value: A Float value equal to Area(Overlap(object1,object2) ) / Area(object1). 2) The ProportionOverlap function will do just this. Just proceed as follows: 1. Query SQL Select 2. Select Columns : ..., ProportionOverlap(YourLayer1.obj,YourLayer2.obj) 3. From Tables YourLayer1, YourLayer2 4. Where YourLayer1.obj Intersects YourLayer2.obj And the results will be a percentage. 3) I've cut and paste a bit of code below. Its not too helpful at first, but it may point you in the right direction. Basically you calculate the percentage overlap using the formula proportion * 100. The code is cut and paste from a program, "table1ColAlias" just means the name of field I want from my "table 1". I have a small MapBasic script here if you don't work it out. Select table1ColAlias, table2ColAlias, Sum(ProportionOverlap(table1ObjAlias,table2ObjAlias)*100), Sum(ProportionOverlap(table2ObjAlias,table1ObjAlias)*100) From table1Name,table2Name Where table1ObjAlias Intersects table2ObjAlias Into qryResult Group by table1ColAlias, table2ColAlias -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Darrin Clement Sent: Monday, February 25, 2002 9:30 PM To: Mapinfo-L@lists. directionsmag. com Subject: MI-L area of overlap Hello, I have two sets (layers) of polygons. For each polygon in Layer1, I want to calculate how much of its area - as a percentage - lies within any polygon in Layer2. (Layer1 polygons are very small, Layer2 polygons are very big and spread out.) Does anyone have advice for how to accomplish this without the MapBasic compiler? Thank you in advance. Darrin ---------------------------------------------------- Sign Up for NetZero Platinum Today Only $9.95 per month! http://my.netzero.net/s/signup?r=platinum&refcd=PT97 ____________________________________________________________ ___________ 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. ---------------------------------------------------- Sign Up for NetZero Platinum Today Only $9.95 per month! http://my.netzero.net/s/signup?r=platinum&refcd=PT97 _______________________________________________________________________ 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.
