GF2::Vector — Change Elements via Function Value
Methods to set or flip the element values in a bit-vector based on the return value from a function call.
constexpr Vector &set_if(std::invocable<std::size_t, std::size_t> auto f); (1)
constexpr Vector &flip_if(std::invocable<std::size_t, std::size_t> auto f); (2)| 1 | Sets element i to 1 if f(i) != 0, otherwise sets it to 0. |
| 2 | Flips the value of element i if f(i) != 0, otherwise leaves it unchanged. |
f is a function that we expect to call as f(i) for each index.
Returns
Both methods return a reference to *this so can be chained with other calls.
Example
#include <GF2/GF2.h>
int main()
{
GF2::Vector<> v(32); (1)
std::cout << "v: " << v << '\n';
v.set_if([](std::size_t i) { return (i + 1) % 2; }); (2)
std::cout << "v: " << v << '\n';
v.flip_if([](std::size_t i) { return (i + 1) % 2; }); (3)
std::cout << "v: " << v << '\n';
}| 1 | Start with a bit-vector whose elements are all 0 by default. |
| 2 | Using the set_if method with a lambda to set the even indices 0,2,4,… |
| 3 | Using the flip_if method with a lambda to flip the even indices 0,2,4,… |
Output
v: 00000000000000000000000000000000
v: 10101010101010101010101010101010
v: 00000000000000000000000000000000