shreyash14s/itertools-c

Python's itertools implementation for C.

Itertools library for C

This is my effort to implement python's itertools library for C.

Methods supported so far -

For creating iterator

• newArrayIter(array, array_length, size_of_element)
• new_list_iter(list)

Itertools library functions

• count(init_val, step)
• cycle(array, array_length, size_of_element)
• repeat(value)
• accumulate(iterator, function, init_val)
• compress(iterator1, iterator2)
• islice(iterator, start, stop, step)

Some other functions

• permutations(array, n, r, size_of_element)
• combinations(array, n, r, size_of_element)
• combinations_replacement(array, n, r, size_of_element)

Example

How to create array iterator -

iter* i = newArrayIter(a, n, sizeof(*a)); // Creates Array iterator.
while(has_next(i))
  printf("%d ", *(int*) next(i));
free_iter(i);

Accumulation example -

int fun(const void* a, const void* b)
{
	return *(int*) a + *(int*) b;
}

...

iter* i = accumulate(iter, fun, 0);   // iter is iterator.
while(has_next(i))
  printf("%d ", *(int*) next(i));   // prints cumulative sum.
free_iter(i);

Permutations -

iter* i = permutations(a, n, r, sizeof(*a));  // a is array
int* c;
printf("Permutations are \n");
while (has_next(i))
{
  c = (int*) next(i);
  for (int j = 0; j < r; j++)
    printf("%d ", c[j]);
  printf("\n");
}
free_iter(i);

How to test

File main.c contains examples of how use this library.

make test           # Make files
./test

To test permutations

make permtest       # Make permutations test
./permtest          # Run it

To test combinations

make combtest       # Make combinations test
./combtest          # Run it

I hope u like it. ;)