How to reorder vector elements in C++? - c++

Question

I have a vector of objects whose elements I want to access in a sequence other than originally stored. My initial thought was to create an array of pointers, one for each array object, and move the pointer values to the desired order (so the underlying array doesn't need to change).
The vector iterator seems similar to an array of pointers, but I couldn't determine if they can be repointed.
Is there a customary way to do this?
ETA:
#doug's comment below sent my mind down another path and I think I was overcomplicating the task. Each object in the array has an attribute that determines the order I want to consume another attribute. Based on doug's suggestion, I could traverse the array and write out two new arrays (one for each attribute) and do a vector of pairs sort. Consistent with #Ted Lyngmo's thought, maybe I could traverse the array and write out a single new array of structures comprised of the two attributes and then do a std::sort.
ETA 2:
In case it matters, the vector of objects is generated by an external library and the attributes are only exposed through method calls.

Answer 1

Despite my poorly composed question, the responses helped me arrive at a solution. As an FYI, here it is:
#include <algorithm>
using namespace std;
//structure to hold select data from array provided by external library
struct outdata
{
string Sort; //data to be sorted
double SortInfo1; //sort criteria1
double SortInfo2; //sort criteria2
} od;
//function used to sort by criteria1 and then by criteria2
bool CompareFunc(const outdata& a, const outdata& b)
{
if (a.SortInfo1 < b.SortInfo1) return true;
if (b.SortInfo1 < a.SortInfo1) return false;
// a=b for SortInfo1, go to SortInfo2
if (a.SortInfo2 < b.SortInfo2) return true;
if (b.SortInfo2 < a.SortInfo2) return false;
return false;
}
int main()
{
vector<obj> source (getarray()); //array provided by external library
vector<outdata> outarray; //array to hold data extracted from source
//traverse source array and load select data to outarray
for (vector<obj>::iterator it = source.begin(); it != source.end(); ++it)
{
od.Sort = it->getSort();
od.SortInfo1 = it->getSortInfo1();
od.SortInfo2 = it->getSortInfo2();
outarray.push_back(od);
}
sort(outarray.begin(), outarray.end(), CompareFunc); //sort outarray
//view results
for (vector<outdata>::iterator it = outarray.begin(); it != outarray.end(); ++it)
{
printf("%s\n", it->Sort.c_str());
}
}