一、兩個經緯度點之間的距離
$phi_1$，$phi_2$是緯度，$lambda_1$，$lambda_2$是經度。均是弧度制數值
ArcGIS Python 實作
2 * 6372 * math.asin(math.sqrt(math.sin((math.radians( !CENTROID_Y! )-math.radians( !Avg_co_lat! ))/2 )**2 + math.cos(math.radians( !CENTROID_Y! ) ) * math.cos(math.radians( !Avg_co_lat! ) ) * math.sin((math.radians( !CENTROID_X! )-math.radians( !Avg_co_lon! ))/2 )**2 ) )
python 實作：
from math import radians, cos, sin, asin, sqrt
def distance(lon1, lat1, lon2, lat2):
lon1, lat1, lon2, lat2 = map(radians, [lon1, lat1, lon2, lat2])
# haversine function
dlon = lon2 - lon1
dlat = lat2 - lat1
a = sin(dlat/2)**2 + cos(lat1) * cos(lat2) * sin(dlon/2)**2
c = 2 * asin(sqrt(a))
r = 6372 # ratio of earch, km
return c * r # km
二、經緯度網格的面積計算
$phi_1$，$phi_2$是緯度，$lambda_1$，$lambda_2$是經度。 均是弧度制數值
python 實作
from math import radians, sin
def area(lon1, lat1, lon2, lat2):
lon1, lat1, lon2, lat2 = map(radians, [lon1, lat1, lon2, lat2])
r = 6372
return abs(r**2 * (lon2 - lon1) * (sin(lat2) - sin(lat1)))