(I am using ArcGIS software, ArcMap...)
I have a shape file containing points. The shape file contains 3 columns named FID, Shape* and Label. In the column I want to fill in AA, AB, AC..., BA, BB, BC...ZZ. Since this is over 600 points (and I have 19 of these shape files), I do not want to do this manually. How do I proceed to fill this in automatically? Preferably by using field calculator.
I would prefer to be able to:
- Select say 100 of the points
- Use field calculator to name them AA-DX
- Make new selection of 100 (or some other count)
- Continue naming them from where I left off. So DY-HT
- Make new selection of 100 ..... and so on...
TRIED SO FAR
What I already have tried is to create a table in excel with a label column and AA, AB, and so on already filled in. And with a FID column filled in with 0, 1, 2, 3... Then I imported that table to ArcMap and joined the shape file to the new table based on the two FID columns. Unfortunately there is no system to the shape files FID column up against what I want them to be named. So what happens when I join is that I have FID 1 = AA, 2 = AB and so on. Whilst what I really want is FID 74 = AA, 35 = AB, and so on in almost a random number.
The excel code I used to generate AA, AB, AC and so on was: =IF(RIGHT(A1)="Z",CHAR(CODE(LEFT(A1))+1),LEFT(A1))&IF(RIGHT(A1)<>"Z",CHAR(CODE(RIGHT(A1))+1),CHAR(65)) I wrote AA in the first cell, and then this code in all underlying cells
To give you a better picture of the problem: I have several points divided on 3 islands. The points were created randomly, so point 1-250 are not all on the same island, and then 251-500 are not on the next same island. The points are just randomly scattered on the three islands. I want to select all points on island 1 and name them AA-DY (or whatever). Then selecting all points on the next island and naming them from DY and on to TG (or whatever). And then continuing on the next Island. Within the one island it does not matter what point becomes AA or what point becomes BR. if that follows FID it is ok but it does not really matter (so if point 2, 6, 12 and 34 were the only islands on the first island. point 2 would be AA, point 6 would be AB, 12 = AC and 34 = AD)
Anybody who can solve my problem?