Template Function thrust::adjacent_difference(InputIterator, InputIterator, OutputIterator)¶

Function Documentation¶

template<typename InputIterator, typename OutputIterator> OutputIterator thrust::adjacent_difference(InputIterator first, InputIterator last, OutputIterator result)

adjacent_difference calculates the differences of adjacent elements in the range [first, last). That is, *first is assigned to *result, and, for each iterator i in the range [first + 1, last), the difference of *i and *(i - 1) is assigned to *(result + (i - first)).

This version of adjacent_difference uses operator- to calculate differences.

The following code snippet demonstrates how to use

adjacent_difference to compute the difference between adjacent elements of a range.

Return

The iterator result + (last - first)

Remark

Note that result is permitted to be the same iterator as first. This is useful for computing differences “in place”.

Parameters

first: The beginning of the input range.
last: The end of the input range.
result: The beginning of the output range.

Template Parameters

InputIterator: is a model of Input Iterator, and x and y are objects of InputIterator's value_type, then x - is defined, and InputIterator's value_type is convertible to a type in OutputIterator's set of value_types, and the return type of x - y is convertible to a type in OutputIterator's set of value_types.
OutputIterator: is a model of Output Iterator.

#include <thrust/adjacent_difference.h>
#include <thrust/device_vector.h>
...
int h_data[8] = {1, 2, 1, 2, 1, 2, 1, 2};
thrust::device_vector<int> d_data(h_data, h_data + 8);
thrust::device_vector<int> d_result(8);

thrust::adjacent_difference(d_data.begin(), d_data.end(), d_result.begin());

// d_result is now [1, 1, -1, 1, -1, 1, -1, 1]

See: http://www.sgi.com/tech/stl/adjacent_difference.html
See: inclusive_scan