在Python中显示按与给定节点的距离排序的节点

Question

I have a number of nodes, each has an x-axis and y-axis values which indicate a distance from each other. For example,

nodes = [
{'name': 'node1', 'x': 2, 'y': 4, 'friend': True},
{'name': 'node2', 'x': -3, 'y': 2, 'friend': True},
{'name': 'node3', 'x': 5, 'y': 0, 'friend': False},
{'name': 'node4', 'x': -6, 'y': 1, 'friend': False},
{'name': 'node5', 'x': 0, 'y': 3, 'friend': True} 
]

I need to create a function that returns only nodes who are friends sorted by a distance to a given node (say main_node = nodes[0] ) based on the X and Y values.

I would appreciate your help.

Answer 1

The sort function takes a key parameter:

main_node = nodes[0]
nodes.sort(key=lambda node: math.hypot(node["x"] - main_node["x"], node["y"] - main_node["y"]))