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Merge with James's changes

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This commit is contained in:
Neil Lawrence 2013-11-21 21:42:09 +00:00
parent f9e2a389e8
commit 1deb1bee86
2 changed files with 3 additions and 28 deletions
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22
GPy/kern/constructors.py
View file

@ -292,7 +292,6 @@ except ImportError:
if sympy_available:
from parts.sympykern import spkern
from sympy.parsing.sympy_parser import parse_expr
from GPy.util.symbolic import sinc
def rbf_sympy(input_dim, ARD=False, variance=1., lengthscale=1.):
"""
@ -337,27 +336,6 @@ if sympy_available:
f = scale_i*scale_j*sp.exp(-dist/(2*(lengthscale_i**2 + lengthscale_j**2 + shared_lengthscale**2)))
return kern(input_dim, [spkern(input_dim, f, output_dim=output_dim, name='eq_sympy')])
def sinc(input_dim, ARD=False, variance=1., lengthscale=1.):
"""
TODO: Not clear why this isn't working, suggests argument of sinc is not a number.
sinc covariance funciton
"""
X = sp.symbols('x_:' + str(input_dim))
Z = sp.symbols('z_:' + str(input_dim))
variance = sp.var('variance',positive=True)
if ARD:
lengthscales = [sp.var('lengthscale_%i' % i, positive=True) for i in range(input_dim)]
dist_string = ' + '.join(['(x_%i-z_%i)**2/lengthscale_%i**2' % (i, i, i) for i in range(input_dim)])
dist = parse_expr(dist_string)
f = variance*sinc(sp.pi*sp.sqrt(dist))
else:
lengthscale = sp.var('lengthscale',positive=True)
dist_string = ' + '.join(['(x_%i-z_%i)**2' % (i, i) for i in range(input_dim)])
dist = parse_expr(dist_string)
f = variance*sinc(sp.pi*sp.sqrt(dist)/lengthscale)
return kern(input_dim, [spkern(input_dim, f, name='sinc')])
def sympykern(input_dim, k=None, output_dim=1, name=None, param=None):
"""
A base kernel object, where all the hard work in done by sympy.

9
GPy/testing/kernel_tests.py
View file

@ -34,12 +34,9 @@ class KernelTests(unittest.TestCase):
self.assertTrue(GPy.kern.kern_test(kern, verbose=verbose))
def test_eq_sympykernel(self):
kern = GPy.kern.eq_sympy(5, 3, output_ind=4)
self.assertTrue(GPy.kern.kern_test(kern, verbose=verbose))
def test_sinckernel(self):
kern = GPy.kern.sinc(5)
self.assertTrue(GPy.kern.kern_test(kern, verbose=verbose))
if SYMPY_AVAILABLE:
kern = GPy.kern.eq_sympy(5, 3, output_ind=4)
self.assertTrue(GPy.kern.kern_test(kern, verbose=verbose))
def test_rbf_invkernel(self):
kern = GPy.kern.rbf_inv(5)