objective c - Sorting an nsmutable array --> order is not being saved? -

kind of noob question maybe: i'm trying sort nsmutablearray, somehow order not being stored.

    typedef struct {         float distance;         int index;     } distanceandindex;     = 0;        nsmutablearray *ordereddistances = [nsmutablearray arraywithcapacity:(self.waypoints.count)]; cllocation* rwp2 = [[cllocation alloc] initwithlatitude:52.080752 longitude:4.7527251];         latlontoecef(rwp2.coordinate.latitude, rwp2.coordinate.longitude, 0.0, &myx, &myy, &myz);          (routewaypoint *rwp in [[self waypoints] objectenumerator]) {             double poix, poiy, poiz, e, n, u;               latlontoecef(rwp.location.coordinate.latitude, rwp.location.coordinate.longitude, 0.0, &poix, &poiy, &poiz);             eceftoenu(rwp2.coordinate.latitude, rwp2.coordinate.longitude, myx, myy, myz, poix, poiy, poiz, &e, &n, &u);              distanceandindex distanceandindex;             distanceandindex.distance = sqrtf(n*n + e*e);             distanceandindex.index = i;              nslog(@"index = %i, %f", i, distanceandindex.distance);             [ordereddistances insertobject:[nsdata datawithbytes:&distanceandindex length:sizeof(distanceandindex)] atindex:i++];         }         i=0;           [ordereddistances sortusingcomparator:(nscomparator)^(nsdata *a, nsdata *b) {             const distanceandindex *adata = (const distanceandindex *)a.bytes;             const distanceandindex *bdata = (const distanceandindex *)b.bytes;               if (adata->distance < bdata->distance) {                 return nsorderedascending;             } else if (adata->distance > bdata->distance) {                 return nsorderedascending;             } else {                 return nsorderedsame;             }         }];           (nsdata *d in [ordereddistances reverseobjectenumerator]) {             const distanceandindex *distanceandindex = (const distanceandindex *)d.bytes;                     nslog(@"item: %i, %f", distanceandindex->index, distanceandindex->distance);         } 

the output following:

[2021:907] waypoints: 8 [2021:907] index = 0, 230.078827

[2021:907] index = 1, 171.626389

[2021:907] index = 2, 36.015743

[2021:907] index = 3, 103.174805

[2021:907] index = 4, 238.837616

[2021:907] index = 5, 278.074371

[2021:907] index = 6, 288.319763

[2021:907] index = 7, 321.953156

[2021:907] item: 7, 321.953156

[2021:907] item: 6, 288.319763

[2021:907] item: 5, 278.074371

[2021:907] item: 4, 238.837616

[2021:907] item: 3, 103.174805

[2021:907] item: 2, 36.015743

[2021:907] item: 1, 171.626389

[2021:907] item: 0, 230.078827

the array hasn't been reordered (for instance when looking @ items 1,2 , 3). feel i'm overlooking basic. ideas?

thanks!

you appear overlooking typo:

       if (adata->distance < bdata->distance) {             return nsorderedascending;         } else if (adata->distance > bdata->distance) {             return nsorderedascending;         } else {             return nsorderedsame;         } 

the second 1 should nsordereddescending, think.