I am trying to make a systematic cluster sampling pattern for data collection. The sampling consist of the points placed over the landscape in 6 km span (red). From this major point, I need to create 3x3 sampling spots in 200 m span (grey), in direction towards the east and south, creating L shaped cluster of points.
I was wondering, how to make this sampling scheme in ArcGIS using ArcPy?
It is pretty straightforward to generate a set of equally distributed points over the landscape using Create Fishnet tool
and set Create Label Points
as TRUE. Cell height and cell width will simply be 6 km.
But do you have any suggestion, how to create set of grey points located towards east and south, in 200 m distance from each other?
I honestly even don't know where to start...
My sample code to generate red grid points:
import arcpy, os
from arcpy import env
# Allow files to overwrite
arcpy.env.overwriteOutput = True
# Set coordinate system of the output fishnet
arcpy.env.outputCoordinateSystem = arcpy.SpatialReference(3067)
# Define working directory
inWD = "C:/Users/data/raw"
# Define variables:
inFC = os.path.join(inWD, "myFC.shp")
outFC = os.path.join(inWD, "myFC_grid.shp")
# Create fishnet
cellSizeWidth = 6000 # 6 km
cellSizeHeight = cellSizeWidth
labels = "LABELS" # Create points in the middle of squares
desc = arcpy.Describe(inFC) # get describe object to define extent coordinates
# Process: Create fishnet
arcpy.CreateFishnet_management(out_feature_class = outFC,
origin_coord = str(desc.extent.lowerLeft),
y_axis_coord = str(desc.extent.XMin) + " " + str(desc.extent.YMax + 100),
cell_width = cellSizeWidth,
cell_height = cellSizeHeight,
number_rows = "0",
number_columns ="0",
corner_coord = str(desc.extent.upperRight),
labels = "LABELS",
template = "#",
geometry_type = "POLYLINE")
print "basic fishnet created"
# Import newly generated point grid data ""
red_points = os.path.join(inWD, "myFC_grid_label.shp")
# Make new freature class to add new points
grey_points = os.path.join(inWD, "Lcluster.shp")
How to add clusters points to grey dataset?