# Easiest way to create measured intervals between shape points

I need to import a scanned photo of the outcrop (geology project) and re-create the grid from which I took plug data- each plug point will be drawn as a shape point file.

The plugs were taken on a metre by metre grid layout. What would be the best way to ensure that the points are evenly spaced on the outcrop photos?- I guess I could mark the points on the scanned photo and then shapefile the marked points.

• What software would you like to do this in? – djq Jan 1 '13 at 17:43
• I will be using ArcGIS 10. The idea is to create a kriging surface between the points using Arc Tool Box. – GISWiltshire Jan 1 '13 at 17:46

``````cur = arcpy.InsertCursor("ticks")

for i in range(int(extent_XMin) ,int( extent_XMax )  , int( interval) ):
for j in range(int(extent_YMin) , int(extent_YMax) , int( interval) ):
pt = arcpy.Point(i , j)
row = cur.newRow()
row.Shape = pt
cur.insertRow(row)
``````

this script creates a grid in "ticks"

• Unfortunately I don't have access to Python on the computer (university restricted access). – GISWiltshire Jan 1 '13 at 18:25
• any way to do it with vb.net ? arcEngine – Mounaim Nov 6 '13 at 12:25
• you can do it via geoprocessing in Arcobjects .NET – geogeek Nov 6 '13 at 16:10

To create a regularly spaced point grid, use Create Fishnet (Data Management). In the attached image, I created a 50x50 fishnet grid. However, you can specify any sized grid you would like--just make sure to check the "Create Label Points" box in the tool.

I should also point out that the regularly spaced point grid approach is appropriate for interpolation methods such as local polynomial interpolation that assume samples were taken on a grid. There are other interpolation methods that do not assume samples were taken on a point grid. Methods such as global polynomial interpolation and empirical bayesian kriging do not have such assumptions. In case you are new to kriging, I would highly recommend going through through the ArcGIS Geostatistical Analyst Tutorial, which is very good.

Edit:

To add points along the feature vertices, use Feature Vertices to Points after you create the fishnet (see below example).

• Ok awesome- the only thing is the data points- they are on each corner, rather than in the centre. Would fishnet allow me to add to the corners? – GISWiltshire Jan 1 '13 at 18:27
• @GISWiltshire I edited the post to address your comments. – Aaron Jan 1 '13 at 18:55
• Great thanks Aaron. I'll give this a go- effectively treating the scanned in photo (cross-sectional view) as a map. Probably pushing the bounds of the function, but do you know if the grid can be angled?- a number of the outcrops are dipping- only at very low angles (max 14). Thanks again. Chris. – GISWiltshire Jan 1 '13 at 19:05
• Try orienting the fishnet by adding coordinates to the "Y-Axis Coordinate" input in the Fishnet tool. – Aaron Jan 1 '13 at 19:19
• Your welcome. Good luck! – Aaron Jan 2 '13 at 0:25