def nearest_node(point, node_set):
''' nearest_node() - Find the nearest node to a point from the node array
** INCOMPLETE **
TODO: NEED TO UPDATE TO READ WELL FILE
Parameters
----------
point : tuple
(x,y) point
node_set : list
list of node numbers with x and y of each
Returns
-------
nearest : int
number of nearest node
'''
import iwfm as iwfm
dist, nearest = 9.9e30, -1
for j in range(0, len(node_set)):
line = node_set[j]
pt = [line[1], line[2]]
# Compute distance between each pair of the two collections of inputs.
new_dist = iwfm.distance(point, pt)
if dist > new_dist:
dist, nearest = new_dist, line[0]
return nearest
def nearest(d_nodes, x, y):
''' nearest() - Find the nearest node to a point from a node dictionary
Parameters
----------
d_nodes : dictionary
key = model node, value = x and y locations
x : float
x location of point
y : float
y location of point
Returns
-------
nearest : int
node ID of node closest to (x,y)
'''
import iwfm as iwfm
point = [x, y]
dist = 9.9e30
nearest = -1
for key in d_nodes:
pt = d_nodes[key]
new_dist = iwfm.distance(point, pt)
if dist > new_dist:
dist = new_dist
nearest = key
return nearest
def iwfm_nearest_nodes(filename, node_set):
''' iwfm_nearest_nodes() - Read a point file, calculate the nearest node
and distance for each point, and write the results to the output file
Parameters
----------
filename : str
output file name base
node_set : list
node IDs and x,y locations
Returns
-------
number of points processed
'''
import iwfm as iwfm
output_filename = filename[0:filename.find('.')] + '_nodes.out'
with open(output_filename, 'w') as output_file:
with open(filename, 'r') as input_file:
lines = input_file.read().splitlines() # open and read input file
output_file.write(f'{lines[0]}\tNdNear\tNdDist\n')
for line_index in range(1, len(lines)): # skip header line
temp = lines[line_index].split()
nearest = iwfm.nearest_node(
[float(temp[1]), float(temp[2])], node_set)
dist = iwfm.distance(
[float(temp[1]), float(temp[2])],
[node_set[nearest][1], node_set[nearest][2]],
)
# write out
output_file.write(f'{lines[line_index]}\t{nearest}\t{dist}\n')
return len(lines) - 1