判断点是否在区域的python实现（射线法）

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# @Date    : 2018-10-07 15:49:37
# @Author  : Sheldon ([email protected])
# @Blog    : 谢耳朵的派森笔记
# @Link    : https://www.cnblogs.com/shld/
# @Version : 0.0.1

def isinpolygon(point,vertex_lst:list, contain_boundary=True):
    #检测点是否位于区域外接矩形内
    lngaxis, lataxis = zip(*vertex_lst)
    minlng, maxlng = min(lngaxis),max(lngaxis)
    minlat, maxlat = min(lataxis),max(lataxis)
    lng, lat = point
    if contain_boundary:      
        isin = (minlng<=lng<=maxlng) & (minlat<=lat<=maxlat)
    else:
        isin = (minlng<lng<maxlng) & (minlat<lat<maxlat)
    return isin

def isintersect(poi,spoi,epoi):
    #输入：判断点，边起点，边终点，都是[lng,lat]格式数组
    #射线为向东的纬线
    #可能存在的bug，当区域横跨本初子午线或180度经线的时候可能有问题
    lng, lat = poi
    slng, slat = spoi
    elng, elat = epoi
    if poi == spoi:
        #print("在顶点上")
        return None
    if slat==elat: #排除与射线平行、重合，线段首尾端点重合的情况
        return False
    if slat>lat and elat>lat: #线段在射线上边
        return False
    if slat<lat and elat<lat: #线段在射线下边
        return False
    if slat==lat and elat>lat: #交点为下端点，对应spoint
        return False
    if elat==lat and slat>lat: #交点为下端点，对应epoint
        return False
    if slng<lng and elat<lat: #线段在射线左边
        return False
    #求交点
    xseg=elng-(elng-slng)*(elat-lat)/(elat-slat)
    if xseg == lng:
        #print("点在多边形的边上")
        return None
    if xseg<lng: #交点在射线起点的左侧
        return False
    return True  #排除上述情况之后

def isin_multipolygon(poi,vertex_lst, contain_boundary=True): 
    # 判断是否在外包矩形内，如果不在，直接返回false    
    if not isinpolygon(poi, vertex_lst, contain_boundary):
        return False
    sinsc = 0        
    for spoi, epoi in zip(vertex_lst[:-1],vertex_lst[1::]):
        intersect = isintersect(poi, spoi, epoi)
        if intersect is None:
            return (False, True)[contain_boundary]
        elif intersect:
            sinsc+=1          
    return sinsc%2==1




if __name__ == '__main__':
    
    vertex_raw = ['113.77253623662,22.734971291583', '113.77255514955,22.73509716357', '113.77655989881,22.736350557773', '113.77676822305,22.73640965307', '113.77736723203,22.736534992321', '113.77940615018,22.736878669244', '113.77947030985,22.736860953444', '113.77949943202,22.736797638175', '113.77996334483,22.734671733626', '113.78003353483,22.734638924801', '113.78109183843,22.734901179433', '113.78111784887,22.734964846247', '113.78115384936,22.735067381603', '113.78114374702,22.735157490465', '113.78107244941,22.73530034639', '113.78095676023,22.735766684331', '113.78094658962,22.735932778191', '113.78103664924,22.736114636979', '113.78116482396,22.736273022099', '113.78134419131,22.736359769194', '113.78211401039,22.73651290222', '113.78222325602,22.736555467145', '113.7823555342,22.73663071491', '113.78248580377,22.736711977153', '113.78259294826,22.736865523263', '113.7826400563,22.736883891204', '113.78273032433,22.73685368898', '113.78357214618,22.735114513862', '113.78288857701,22.734768949082', '113.78456713092,22.731111070805', '113.78499799148,22.730246917863', '113.78507426121,22.730178805366', '113.7855499059,22.72982978801', '113.7855439672,22.729710894129', '113.78547284386,22.729577977108', '113.78485039809,22.72898526075', '113.7844013172,22.728642818037', '113.78407147738,22.728484550981', '113.78369248319,22.728371904397', '113.7832943991,22.728348425846', '113.78279101654,22.728381265282', '113.78223548106,22.728490624284', '113.78120871157,22.728746702049', '113.78070843445,22.728835826604', '113.78028539185,22.728892874896', '113.77960479337,22.728941739674', '113.77917585519,22.728917533458', '113.77850550189,22.728784767411', '113.77800554816,22.728664945674', '113.77713301773,22.728385531131', '113.77575487604,22.727878867397', '113.77366621063,22.727101561255', '113.77346692784,22.72714784993', '113.77333268596,22.727276687378', '113.77266852558,22.733599777451', '113.77264730132,22.73384585746', '113.77253623662,22.734971291583']
    vertex_lst = [[float(strnum) for strnum in poistr.split(",")] for poistr in vertex_raw]
    poi = [113.7726,22.735]
    print(isin_multipolygon(poi,vertex_lst, contain_boundary=True))