devel_numpy_c_api_cython

NumPy ndarray sum (Cython)

Typed NumPy ndarray access.

# cython: language_level=3

"""Devel Cython template: NumPy ndarray typed access.

Requires NumPy.
"""

cimport numpy as cnp
import numpy as np


def sum_ndarray(object arr):
    cdef cnp.ndarray[cnp.double_t, ndim=1] x = np.asarray(arr, dtype=np.float64)
    cdef Py_ssize_t i
    cdef double s = 0.0
    for i in range(x.shape[0]):
        s += x[i]
    return s

Devel NumPy: typed ndarray

cimport numpy example.

# cython: language_level=3
"""Devel NumPy C-API Cython template.

Requires NumPy at compile time.
"""

# import numpy as np
cimport numpy as cnp


def sum_float64(cnp.ndarray[cnp.float64_t, ndim=1] x):
    cdef Py_ssize_t i, n = x.shape[0]
    cdef double s = 0.0
    for i in range(n):
        s += x[i]
    return s

Sum NumPy 1D array

# cython: language_level=3
"""
Sum a 1D NumPy array using typed memoryviews.

Requires NumPy (template metadata marks it).
"""

# import numpy as np
cimport numpy as cnp
cnp.import_array()


cpdef double sum1d(cnp.ndarray[cnp.double_t, ndim=1] x):
    cdef Py_ssize_t i, n = x.shape[0]
    cdef double acc = 0.0
    for i in range(n):
        acc += <double>x[i]
    return acc

Sum NumPy 1D array

# cython: language_level=3
"""
Sum a 1D NumPy array using typed memoryviews.

Requires NumPy (template metadata marks it).
"""
# import numpy as np
cimport numpy as cnp
cnp.import_array()

cpdef double sum1d(cnp.ndarray[cnp.double_t, ndim=1] x):
    cdef Py_ssize_t i, n = x.shape[0]
    cdef double acc = 0.0
    for i in range(n):
        acc += <double>x[i]
    return acc

Sum NumPy 1D array

# cython: language_level=3
"""
Sum a 1D NumPy array using typed memoryviews.

Requires NumPy (template metadata marks it).
"""
import numpy as np  # no-cython-lint
cimport numpy as cnp
cnp.import_array()

cpdef double sum1d(cnp.ndarray[cnp.double_t, ndim=1] x):
    cdef Py_ssize_t i, n = x.shape[0]
    cdef double acc = 0.0
    for i in range(n):
        acc += <double>x[i]
    return acc