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I want my area filled radomly with a number of points with a number of random numerical values in the range i specify. Other than tediously creating each point and filling up random values, is there any better method?

4

If you have an Advanced license or Spatial Analyst or 3D Analyst, you can use the Create Random Points tool.

You can then add a field and populate it with random values within a specified range with this Python code snippet (change the fc, field_name and range values, then copy-paste the code in the Python window in ArcMap or ArcCatalog):

import arcpy, random
with arcpy.da.UpdateCursor(fc, "field_name") as cur:
    for row in cur:
        row[0] = random.randint(0, 100)
        cur.updateRow(row)

This will generate integer values between 0 and 100. Python offers other random functions if you need another type of range.

  • Thanks. Generating random points was easy. But I am not being able to generate random values for those points. When I use the expression you gave, all the values of the field get populated by a single random value. There is no variation in its value. How do I solve this problem? – Aakash Bikram Rana Sep 29 '16 at 11:29
  • Sorry, I've modified my answer to generate different random values for each row. Using Python is necessary for this. – GISGe Sep 29 '16 at 11:41
  • By the way, which version of ArcGIS do you use? The Calculate Field expression I first suggested should work, but there is a bug in 10.2.1 - which doesn't seem to be solved yet anyway. – GISGe Sep 29 '16 at 11:52
  • Its 10.3 but your code is not working. Could you see what mistake I did? I know nothing of python u know and I am new in GIS too. >>> import arcpy, random ... with arcpy.da.UpdateCursor("random_points","rainfall_in_mm") as cur: ... for row in cur: ... row[0]=random.randint(1000, 1400) ... cur.updateRow(row) ... Parsing error IndentationError: unexpected indent (line 1) >>> – Aakash Bikram Rana Sep 29 '16 at 12:04
  • Make sure you respect the structure, indentation is important with Python: 0 tabs at line 1 and 2 - 1 tab at line 3 - 2 tabs at lines 4 & 5. – GISGe Sep 29 '16 at 12:07

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