我想计算两个数组中所有坐标对之间的距离。以下是我写的一些代码:
def haversine(x,y):
"""
Calculate the great circle distance between two points
on the earth (specified in decimal degrees)
"""
# convert decimal degrees to radians
print(type(x))
lat1, lon1 = np.radians(x)
lat2, lon2 = np.radians(y)
# haversine formula
dlon = lon2 - lon1
dlat = lat2 - lat1
a = np.sin(dlat/2)**2 + np.cos(lat1) * np.cos(lat2) * np.sin(dlon/2)**2
c = 2 * np.arcsin(np.sqrt(a))
r = 6371 # Radius of earth in kilometers. Use 3956 for miles
return c * r
haversine = np.vectorize(haversine)
阵列是
gas_coords
和
postal_coords
.注意
type(postal_coords)
>>>numpy.ndarray
type(gas_coords)
>>>numpy.ndarray
每个数组都有两列。
当我试图计算距离时
using scipy.spatial.distance.cdist
我得到以下错误:
in haversine(x, y)
6 # convert decimal degrees to radians
7 print(type(x))
---->; 8 lat1,lon1 =np.radians(x)
9 lat2,lon2 = np.radians(y)
10
TypeError: 'numpy.float64' object is not iterable
haversine
似乎认为输入
x
是浮点而不是数组。即使当我将数组传递到
哈弗斯林
喜欢
haversine(np.zeros(2),np.zeros(2))
同样的问题也出现了。我应该注意到,这只发生在矢量化通过
np.vectorize
.
从看
哈弗斯林
,参数不会以任何方式更改。导致错误的原因是什么?
下面是一个最小的工作示例:
import numpy as np
from scipy.spatial.distance import cdist
gas_coords = np.array([[50, 80], [50, 81]])
postal_coords = np.array([[51, 80], [51, 81]])
cdist(postal_coords, gas_coords, metric = haversine)
>>>array([[ 111.19492664, 131.7804742 ],
[ 131.7804742 , 111.19492664]])