I am currently writing some code where I have a list of objects with a
maximum occupancy of 4. I have been employing std::vector for this but
I was wondering how much overhead is involved. Is it better to use
some other data structure if speed is critical i.e. maybe a struct
like this-
template <typename T>
struct max_four
{
int element_count;
T elements[4];
};
Or are std::vectors/lists reasonably competitive in both space/time?
Thanks in advance,
Carter. 3 2114
Carter wrote:
I am currently writing some code where I have a list of objects with a
maximum occupancy of 4. I have been employing std::vector for this but
I was wondering how much overhead is involved. Is it better to use
some other data structure if speed is critical i.e. maybe a struct
like this-
template <typename T>
struct max_four
{
int element_count;
T elements[4];
};
Or are std::vectors/lists reasonably competitive in both space/time?
The answer basically depends on how good your dynamic memory mananger
is. I would venture a guess, however, that no dynamic allocation is
better than any dynamic memory allocation.
V
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On May 12, 6:58*pm, Carter <carterch...@gm ail.comwrote:
I am currently writing some code where I have a list of objects with a
maximum occupancy of 4. I have been employing std::vector for this but
I was wondering how much overhead is involved. Is it better to use
some other data structure if speed is critical i.e. maybe a struct
like this-
template <typename T>
struct max_four
{
* * * int element_count;
* * * T elements[4];
};
Or are std::vectors/lists reasonably competitive in both space/time?
A fixed-size container class such as std::tr1::array <(or
boost::array<>) would no doubt be more efficient than using a
dynamically-sized container such as a std::vector or a std::list. I
doubt however that the overhead saved would be meaningful; you would
have to profile your program's performance to find out for certain.
Greg
Thanks I might give the boost::array<a try. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics |
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