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From: Ramon F Herrera on 6 Nov 2009 15:54

I have used this feature in other programming languages, such as Java
and Perl but not in C++.

I have a basic struct which contains an amount and a date. Then I have
an aggregate (should I use a list or a vector?) of the basic struct. I
need to sort the {list, vector} based on one of the above mentioned
fields.

An example would be nice.

Thx,

-RFH

From: Ramon F Herrera on 6 Nov 2009 19:59
On Nov 6, 4:54 pm, Ramon F Herrera <ra...(a)conexus.net> wrote:
> I have used this feature in other programming languages, such as Java
> and Perl but not in C++.
>
> I have a basic struct which contains an amount and a date. Then I have
> an aggregate (should I use a list or a vector?) of the basic struct. I
> need to sort the {list, vector} based on one of the above mentioned
> fields.
>
> An example would be nice.
>
> Thx,
>
> -RFH


I already discovered algorithm::sort(), so it looks like instead of
using a list or a vector, I should use an old fashioned array?

-RFH

From: LR on 6 Nov 2009 22:42
Ramon F Herrera wrote:
>
> I have used this feature in other programming languages, such as Java
> and Perl but not in C++.
>
> I have a basic struct which contains an amount and a date. Then I have
> an aggregate (should I use a list or a vector?) of the basic struct. I
> need to sort the {list, vector} based on one of the above mentioned
> fields.
>
> An example would be nice.

I googled(tm) for
sort struct in c++ -bubble
and found
http://www.daniweb.com/forums/thread178418.html

LR
From: Francis Glassborow on 7 Nov 2009 02:23
Ramon F Herrera wrote:
> On Nov 6, 4:54 pm, Ramon F Herrera <ra...(a)conexus.net> wrote:
>> I have used this feature in other programming languages, such as Java
>> and Perl but not in C++.
>>
>> I have a basic struct which contains an amount and a date. Then I have
>> an aggregate (should I use a list or a vector?) of the basic struct. I
>> need to sort the {list, vector} based on one of the above mentioned
>> fields.
>>
>> An example would be nice.
>>
>> Thx,
>>
>> -RFH
>
>
> I already discovered algorithm::sort(), so it looks like instead of
> using a list or a vector, I should use an old fashioned array?
>
> -RFH
>

If you read the documentation on sort you will find that it works fine
on a std::vector. By default it sorts using 'less than' (assuming
operator < has been defined for the type) but you can provide a
comparison function as the last (optional) argument.
From: Jeff Schwab on 7 Nov 2009 11:02
Ramon F Herrera wrote:

> I have a basic struct which contains an amount and a date. Then I have
> an aggregate (should I use a list or a vector?)

It depends. :) The standard specifically says that all things being
equal, you should usually choose vector. vector has more flexible
iterators, uses contiguous memory, and has some other nice properties.

> of the basic struct. I
> need to sort the {list, vector} based on one of the above mentioned
> fields.

See:
http://www.sgi.com/tech/stl/sort.html
http://www.sgi.com/tech/stl/stable_sort.html

> An example would be nice.

#include <algorithm>
#include <cstdlib>
#include <iterator>
#include <list>
#include <vector>

namespace {

typedef long integer_t;

struct point_t
{
integer_t x;
integer_t y;
};

point_t make_random_point() {
point_t const result = { std::rand(), std::rand() };
return result;
}

bool x_less(point_t const& a, point_t const& b) {
return a.x < b.x;
}
}

int main() {

std::size_t const size = 20;

std::vector<point_t> vec( size );
std::generate(vec.begin(), vec.end(), make_random_point);
std::sort(vec.begin(), vec.end(), x_less);

std::list<point_t> lst;
std::generate_n(back_inserter(lst), size, make_random_point);
lst.sort(x_less);

return EXIT_SUCCESS;
}
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