作业帮助：Python如何使用long和lat确定推文的来源

Question

REALLY confused about a section from my homework, its not graded or anything but I still want to be able to complete and understand it.

I'm trying to "approximate" regions corresponding to their timezones (not real data). So Eastern ( P1. P2. P3, P4 , Pacific( P7, P8, P9, P10 ), Mountain ( P5, P6, P7, P8 ) , Central( P3,P4,P5,P6 )....

im trying to determine the origin of a tweet, by determining which region the latitude and longitude of the tweet belongs (I have a txt file and all the tweets have a long, lat number associated with it. for example: [36.970152730000002, -84.090040380000005] 4 2011-09-02 17:40:11 Chicken flatheads at taco bell my life is complete) . The values of the points are: (rectangle)

p1 = (49.189787, -67.444574) 
p2 = (24.660845, -67.444574)
p3 = (49.189787, -87.518395) 
p4 = (24.660845, -87.518395) 
p5 = (49.189787, -101.998892)
p6 = (24.660845, -101.998892) 
p7 = (49.189787, -115.236428) 
p8 = (24.660845, -115.236428) 
p9 = (49.189787, -125.242264)
p10 = (24.660845, -125.242264)

For example, if a tweet is inbetween p1, p2, p3, p4 then they are from Eastern. How would I do this?

Yes, this is apart of homework, and I know sometimes you guys dont like assissting with homework especially if nothing is provided. But I emailed my teacher 5 hours ago and he stil hasn't responded even though he promised he would reply by tonight (12:48am here)

Answers would be appreciated with explanations but even comments would help :) Its a long assignment and I finished 95% just this part is needed..but im just confused as to the long, lat business.

Answer 1

Assuming the regions are rectangles.

Just check the value of the lat, long against the "border" values.

So, for Eastern:

if lat >= 24.660845 and lat < 49.189787 and long <= -67.444574 and long > -87.518395:
    return True 

Or, if the regions are sequential as you've shown (and only changing in longitude), just check that.

Of course, if the regions are irregular polygons, it would be a whole new problem.

Edit : One approach would be to create a Region class with a contains(lat, long) method:

class Region:
    def __init__(self, lat_tuple, long_tuple):
        self.lat_tuple = lat_tuple
        self.long_tuple = long_tuple

    def contains(self, lat, long):
        return self.lat_tuple[0] <= lat and lat < self.lat_tuple[1] and\
               self.long_tuple[0] <= long and long < self.long_tuple[1]

And use it as:

eastern = Region((24.660845, 49.189787), (-87.518395, -67.444574))
print(eastern.contains(34.0, - 70.10))
print(eastern.contains(14.0, - 70.10))