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core-locationcllocationequatable

How can I compare CLLocationCoordinate2D


I need a way of comparing two CLLocationCoordinate2D's however when I tried using == it wouldn't work. Please can someone help me out with the best way of comparing them?


Solution

  • Either the generic approach for comparing two instances of any given struct type:

    memcmp(&cllc2d1, &second_cllc2d, sizeof(CLLocationCoordinate2D))
    

    or

    cllc2d1.latitude == cllc2d2.latitude && cllc2d1.longitude == cllc2d2.longitude
    

    should work, if you really want to be sure they're exactly equal. However, given that latitude and longitude are defined as doubles, you might really want to do a "close enough" comparison:

    fabs(cllc2d1.latitude - cllc2d2.latitude) <= epsilon && fabs(cllc2d1.longitude - cllc2d2.longitude) <= epsilon
    

    where epsilon is whatever level of error you want to accept.