GPy/GPy/kern/_src/stationary_cython.pyx
2015-05-19 16:54:02 +01:00

59 lines
2 KiB
Cython

#cython: boundscheck=False
#cython: nonecheck=False
#cython: wraparound=False
import numpy as np
cimport numpy as np
from cython.parallel import prange
ctypedef np.float64_t DTYPE_t
cdef extern from "stationary_utils.h":
void _grad_X "_grad_X" (int N, int D, int M, double* X, double* X2, double* tmp, double* grad)
cdef extern from "stationary_utils.h":
void _lengthscale_grads "_lengthscale_grads" (int N, int M, int Q, double* tmp, double* X, double* X2, double* grad)
def grad_X(int N, int D, int M,
np.ndarray[DTYPE_t, ndim=2] _X,
np.ndarray[DTYPE_t, ndim=2] _X2,
np.ndarray[DTYPE_t, ndim=2] _tmp,
np.ndarray[DTYPE_t, ndim=2] _grad):
cdef double *X = <double*> _X.data
cdef double *X2 = <double*> _X2.data
cdef double *tmp = <double*> _tmp.data
cdef double *grad = <double*> _grad.data
_grad_X(N, D, M, X, X2, tmp, grad) # return nothing, work in place.
def grad_X_cython(int N, int D, int M, double[:,:] X, double[:,:] X2, double[:,:] tmp, double[:,:] grad):
cdef int n,d,nd,m
for nd in prange(N*D, nogil=True):
n = nd/D
d = nd%D
grad[n,d] = 0.0
for m in range(M):
grad[n,d] += tmp[n,m]*(X[n,d]-X2[m,d])
def lengthscale_grads_in_c(int N, int M, int Q,
np.ndarray[DTYPE_t, ndim=2] _tmp,
np.ndarray[DTYPE_t, ndim=2] _X,
np.ndarray[DTYPE_t, ndim=2] _X2,
np.ndarray[DTYPE_t, ndim=1] _grad):
cdef double *tmp = <double*> _tmp.data
cdef double *X = <double*> _X.data
cdef double *X2 = <double*> _X2.data
cdef double *grad = <double*> _grad.data
_lengthscale_grads(N, M, Q, tmp, X, X2, grad) # return nothing, work in place.
def lengthscale_grads(int N, int M, int Q, double[:,:] tmp, double[:,:] X, double[:,:] X2, double[:] grad):
cdef int q, n, m
cdef double gradq, dist
for q in range(Q):
grad[q] = 0.0
for n in range(N):
for m in range(M):
dist = X[n,q] - X2[m,q]
grad[q] += tmp[n,m]*dist*dist