Thanks for the tip. I also am trying to measure distance between centroids. I have tried several syntax commands, that are "correct, but don't produce results.
Here is a summary of my efforts if someone can help. Goal: I need to show the distance between each person's unique home address and a specific unique addresses each person attends away from home (called PL1) Steps: 1) I geocoded and created centroids for two places 1) Home and Place1 respectively. 2) The geocoded and centroids for Home and Place1 were in separate tables, so I queried them into one table (called Radom_hempstead_Home_PL1) by the ID#s for each person from both tables. 3) I tried to run the following distance functions, but get no column with the distance between the two places. I get a column of zeros. The centroids between the HomeX, Home Y, Place1, Place1 are difference so the distance should't be zero. Here is the synax I used: _______________________________________ select columns: * >From tables: Radom_hempstead_Home_PL1 Where condition is: distance ( XCoord_Home , YCoord_Home , XCoord_PL1, YCoord_PL1 , "ft") into Table Named: selection ____________________________________________________________ I also tried "mi" which didn't work either. Any suggestions ----- Original Message ----- From: "Woody Woodruff" <[EMAIL PROTECTED]> To: "Neil Evans" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Monday, February 02, 2004 8:47 AM Subject: RE: MI-L FW: Measuring distance between two points. > Distance()function help: > Distance( num_x , num_y , num_x2 , num_y2 , str ) > Returns the distance between two locations. The first two parameters specify > the x and y value of the start location; the next two parameters specify the > x and y value of the end location; the str parameter is a distance unit > name, such as "mi" or "km". > > I use teh mnomoc Latty Fatty Y to rember which is which > > Without writing an mbx, you will need lat and long (y and x) columns for the > objects, use update with centroid(x) and agian for centroid(y). > > Depending on what 2 items you want to generte diatnces for, there are > different stratigies. If its distance to a set of objects from one object > (One store to many customers) use the actuall lat and long in the first part > of the distance function and the fields Lattitude and Longitude for set of > points in a calculated query. I used teh Customer ID and the fields LAT and > LONG for each customer location, and the known position of the store > (-84.82, 45.59) See below. the "Distance_To_Store" part is an alias to > label the column with, other wise the formula will be the Column heading. > > > > some mapbasic text to show the steps > > Alter Table "My_table" ( add Latitude Decimal(13,8) ) > Alter Table "My_table" ( add Longitude Decimal(13,8) ) > > Update My_table Set Latitude = Centroid(y) > Update My_table Set Longitude = Centroid(x) > > Select ID, Distance(-84.82, 43.59,LONG,LAT,"mi") "Distance _To_Store" from > My_table into Selection > > This generates a list of Customer IDs and the distance to the store from > each customer Lat and Long. > > > > William "Woody" Woodruff > Zoning Administrator > Charter Township of Union, Isabella County, Michigan > -84.80947000 43.61095100 > 2010 S Lincoln Rd, Mt. Pleasant, MI 48858 > (989) 772 4600 EXT 41 > Visit our web site at http://www.geocities.com/ctuzoning/index.htm > > > -----Original Message----- > From: Neil Evans [mailto:[EMAIL PROTECTED] > Sent: February 03, 2004 07:15 > To: [EMAIL PROTECTED] > Subject: MI-L FW: Measuring distance between two points. > > > > > Simple peace, how do you measure distance between two points. Someone > remind me what to do again. > > > > Thanks for very much for your help > > Neil > > > > > > > > > > --------------------------------------------------------------------- > List hosting provided by Directions Magazine | www.directionsmag.com | > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > Message number: 10228 > > --------------------------------------------------------------------- List hosting provided by Directions Magazine | www.directionsmag.com | To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Message number: 10320
