{{py:

dtypes = [

('', 'DTYPE_t'),

('32', 'np.float32_t'),

]

}}

cimport numpy as np

from libc.math cimport sqrt, exp

from ..utils._typedefs cimport DTYPE_t, ITYPE_t

{{for name_suffix, DTYPE_t in dtypes}}

######################################################################

# Inline distance functions

#

# We use these for the default (euclidean) case so that they can be

# inlined. This leads to faster computation for the most common case

cdef inline {{DTYPE_t}} euclidean_dist{{name_suffix}}(const {{DTYPE_t}}* x1, const {{DTYPE_t}}* x2,

ITYPE_t size) nogil except -1:

cdef {{DTYPE_t}} tmp, d=0

cdef np.intp_t j

for j in range(size):

tmp = x1[j] - x2[j]

d += tmp * tmp

return sqrt(d)

cdef inline {{DTYPE_t}} euclidean_rdist{{name_suffix}}(const {{DTYPE_t}}* x1, const {{DTYPE_t}}* x2,

ITYPE_t size) nogil except -1:

cdef {{DTYPE_t}} tmp, d=0

cdef np.intp_t j

for j in range(size):

tmp = x1[j] - x2[j]

d += tmp * tmp

return d

cdef inline {{DTYPE_t}} euclidean_dist_to_rdist{{name_suffix}}(const {{DTYPE_t}} dist) nogil except -1:

return dist * dist

cdef inline {{DTYPE_t}} euclidean_rdist_to_dist{{name_suffix}}(const {{DTYPE_t}} dist) nogil except -1:

return sqrt(dist)

######################################################################

# DistanceMetric base class

cdef class DistanceMetric{{name_suffix}}:

# The following attributes are required for a few of the subclasses.

# we must define them here so that cython's limited polymorphism will work.

# Because we don't expect to instantiate a lot of these objects, the

# extra memory overhead of this setup should not be an issue.

cdef {{DTYPE_t}} p

cdef {{DTYPE_t}}[::1] vec

cdef {{DTYPE_t}}[:, ::1] mat

cdef ITYPE_t size

cdef object func

cdef object kwargs

cdef {{DTYPE_t}} dist(self, const {{DTYPE_t}}* x1, const {{DTYPE_t}}* x2,

ITYPE_t size) nogil except -1

cdef {{DTYPE_t}} rdist(self, const {{DTYPE_t}}* x1, const {{DTYPE_t}}* x2,

ITYPE_t size) nogil except -1

cdef int pdist(self, const {{DTYPE_t}}[:, ::1] X, {{DTYPE_t}}[:, ::1] D) except -1

cdef int cdist(self, const {{DTYPE_t}}[:, ::1] X, const {{DTYPE_t}}[:, ::1] Y,

{{DTYPE_t}}[:, ::1] D) except -1

cdef {{DTYPE_t}} _rdist_to_dist(self, {{DTYPE_t}} rdist) nogil except -1

cdef {{DTYPE_t}} _dist_to_rdist(self, {{DTYPE_t}} dist) nogil except -1

######################################################################

# DatasetsPair base class

cdef class DatasetsPair{{name_suffix}}:

cdef DistanceMetric{{name_suffix}} distance_metric

cdef ITYPE_t n_samples_X(self) nogil

cdef ITYPE_t n_samples_Y(self) nogil

cdef {{DTYPE_t}} dist(self, ITYPE_t i, ITYPE_t j) nogil

cdef {{DTYPE_t}} surrogate_dist(self, ITYPE_t i, ITYPE_t j) nogil

cdef class DenseDenseDatasetsPair{{name_suffix}}(DatasetsPair{{name_suffix}}):

cdef:

const {{DTYPE_t}}[:, ::1] X

const {{DTYPE_t}}[:, ::1] Y

ITYPE_t d

{{endfor}}