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# tag: openmp
# You can ignore the previous line.
# It's for internal testing of the cython documentation.

# distutils: extra_compile_args=-fopenmp
# distutils: extra_link_args=-fopenmp

import numpy as np
cimport cython
from cython.parallel import prange

ctypedef fused my_type:
    int
    double
    long long


# We declare our plain c function nogil
cdef my_type clip(my_type a, my_type min_value, my_type max_value) nogil:
    return min(max(a, min_value), max_value)


@cython.boundscheck(False)
@cython.wraparound(False)
def compute(my_type[:, ::1] array_1, my_type[:, ::1] array_2, my_type a, my_type b, my_type c):

    cdef Py_ssize_t x_max = array_1.shape[0]
    cdef Py_ssize_t y_max = array_1.shape[1]

    assert tuple(array_1.shape) == tuple(array_2.shape)

    if my_type is int:
        dtype = np.intc
    elif my_type is double:
        dtype = np.double
    elif my_type is cython.longlong:
        dtype = np.longlong

    result = np.zeros((x_max, y_max), dtype=dtype)
    cdef my_type[:, ::1] result_view = result

    cdef my_type tmp
    cdef Py_ssize_t x, y

    # We use prange here.
    for x in prange(x_max, nogil=True):
        for y in range(y_max):

            tmp = clip(array_1[x, y], 2, 10)
            tmp = tmp * a + array_2[x, y] * b
            result_view[x, y] = tmp + c

    return result