thrust::replace_copy_if

Defined in thrust/replace.h

template<typename DerivedPolicy, typename InputIterator, typename OutputIterator, typename Predicate, typename T> OutputIterator thrust::replace_copy_if(const thrust::detail::execution_policy_base<DerivedPolicy> &exec, InputIterator first, InputIterator last, OutputIterator result, Predicate pred, const T &new_value)

replace_copy_if copies elements from the range [first, last) to the range [result, result + (last-first)), except that any element for which pred is true is not copied; new_value is copied instead.

More precisely, for every integer n such that 0 <= n < last-first, replace_copy_if performs the assignment *(result+n) = new_value if pred(*(first+n)), and *(result+n) = *(first+n) otherwise.

The algorithm’s execution is parallelized as determined by exec.

#include <thrust/replace.h>
#include <thrust/device_vector.h>
#include <thrust/execution_policy.h>

struct is_less_than_zero
{
  __host__ __device__
  bool operator()(int x)
  {
    return x < 0;
  }
};

...

thrust::device_vector<int> A(4);
A[0] =  1;
A[1] = -3;
A[2] =  2;
A[3] = -1;

thrust::device_vector<int> B(4);
is_less_than_zero pred;

thrust::replace_copy_if(thrust::device, A.begin(), A.end(), B.begin(), pred, 0);

// B contains [1, 0, 2, 0]

See also

replace

See also

replace_if

See also

replace_copy

Parameters

exec – The execution policy to use for parallelization.
first – The beginning of the sequence to copy from.
last – The end of the sequence to copy from.
result – The beginning of the sequence to copy to.
pred – The predicate to test on every value of the range [first,last).
new_value – The replacement value to assign pred(*i) evaluates to true.

Template Parameters

DerivedPolicy – The name of the derived execution policy.
InputIterator – is a model of Input Iterator, and InputIterator's value_type is convertible to Predicate's argument type.
OutputIterator – is a model of Output Iterator.
Predicate – is a model of Predicate.
T – is a model of Assignable, and T is convertible to OutputIterator's value_type.

Returns

result + (last-first)

Pre

first may equal result, but the ranges [first, last) and [result, result + (last - first)) shall not overlap otherwise.