distance.py 文件源码

def cal_distance(s,t):
    #s,t = sorted([s,t])
    #if (s,t) in cdic:
    #    return cdic[(s,t)]
    if s in cdic:
        lat1,lon1 = cdic[s]
    else:
        lat1,lon1 = decode(s)
        cdic[s] = (lat1,lon1)

    if t in cdic:
        lat2,lon2 = cdic[t]
    else:
        lat2,lon2 = decode(t)
        cdic[t] = (lat2,lon2)

    #lat2,lon2 = decode(t)
    dx = abs(lon1 - lon2)  
    dy = abs(lat1 - lat2)  
    b = (lat1 + lat2) / 2.0
    Lx = 6371004.0 * (dx / 57.2958) * cos(b / 57.2958)
    Ly = 6371004.0 * (dy / 57.2958)
    L = (Lx**2 + Ly**2) ** 0.5
    cdic[(s,t)] = L
    return L