resolution = 7 # default resolution
# vary resolution based on area so bigger areas have bigger cells
if area < 10:
resolution = 12
elif area > 10 and area < 1000.0:
resolution = 8
elif area > 1000.0 and area < 30000.0:
resolution = 6
elif area > 30000:
resolution = 4
print('using resolution ', resolution)
# calculate the approx cell width at this resolution
thisWidthApprox = rdggs.cell_width(
resolution, plane=True
) # note only approx because we are using the planar to estimate elipsoidal
print('++++++++++ Cell width approx +++', thisWidthApprox, 'm')
thisLGA = feature.record[1]
thisName = feature.record[2]
# call the "call_DGGS" function to return all the DGGS cells (within polygon only)
cells_in_poly = call_DGGS.poly_to_DGGS_tool(polyShape, polyRecord,
resolution)
print('number in polygon = ', len(cells_in_poly))
print('Reducing . . . ')
# reduce to biggest cells
theseReducedCells = call_DGGS.coalesce(cells_in_poly)
#print('reduced cells =', theseReducedCells)
print('number reduced cells =', len(theseReducedCells))
longi = float(row[4])
lati = float(row[3])
# feed lat long into convertor
#Pick a (longitude-latitude) point on the ellipsoid and find the cell that contains it ::
t = (longi, lati)
#figure resolution to use using longitude
strLongi = str(longi) # convert longi to string
strLati = str(lati)
resolution = 10
plane = False # on curve
w = rdggs.cell_width(resolution)
if plane:
area = w**2
else:
area = 8 / (3 * math.pi) * w**2
# change to metres with one decimal place
w = (" %2.0f m" % (w))
# print ()
# calculate the dggs cell from long and lat ie t
thisCell = rdggs.cell_from_point(
resolution, t, plane=False) # false = on the curve
dggsCell = str(thisCell)
#find the boundary for exporting into ESRI or GDAL