Template Function thrust::uninitialized_fill_n(ForwardIterator, Size, const T&)

Function Documentation

template<typename ForwardIterator, typename Size, typename T>
ForwardIterator thrust::uninitialized_fill_n(ForwardIterator first, Size n, const T &x)

In thrust, the function thrust::device_new allocates memory for an object and then creates an object at that location by calling a constructor. Occasionally, however, it is useful to separate those two operations. If each iterator in the range [first, first+n) points to uninitialized memory, then uninitialized_fill creates copies of x in that range. That is, for each iterator i in the range [first, first+n), uninitialized_fill creates a copy of x in the location pointed to i by calling ForwardIterator's value_type's copy constructor.

The following code snippet demonstrates how to use

uninitialized_fill to initialize a range of uninitialized memory.

Return

first+n

Parameters

• first: The first element of the range of interest.

• n: The size of the range of interest.

• x: The value to use as the exemplar of the copy constructor.

Template Parameters

• ForwardIterator: is a model of Forward Iterator, ForwardIterator is mutable, and ForwardIterator's value_type has a constructor that takes a single argument of type T.

#include <thrust/uninitialized_fill.h>
#include <thrust/device_malloc.h>

struct Int
{
  __host__ __device__
  Int(int x) : val(x) {}
  int val;
};  
...
const int N = 137;

Int val(46);
thrust::device_ptr<Int> array = thrust::device_malloc<Int>(N);
thrust::uninitialized_fill_n(array, N, val);

// Int x = array[i];
// x.val == 46 for all 0 <= i < N

See

http://www.sgi.com/tech/stl/uninitialized_fill.html

See

uninitialized_fill

See

fill

See

uninitialized_copy_n

See

device_new

See

device_malloc