def ntm_address(opt, wprev_bhn, M_bnm, k_bhm, beta_bh, g_bh, s_bh3, gamma_bh):
# Content addressing
# Cosine similarity
# take inner product along memory axis k * M
numer_bhn = cgt.einsum("bhm,bnm->bhn", k_bhm, M_bnm)
# compute denominator |k| * |m|
denom_bhn = cgt.broadcast(
"*",
cgt.norm(k_bhm, axis=2, keepdims=True), # -> shape bh1
cgt.norm(M_bnm, axis=2, keepdims=True).transpose([0, 2,
1]), # -> bn1 -> b1n
"xx1,x1x")
csim_bhn = numer_bhn / denom_bhn
assert infer_shape(csim_bhn) == (opt.b, 2 * opt.h, opt.n)
# scale by beta
tmp_bhn = cgt.broadcast("*", beta_bh[:, :, None], csim_bhn, "xx1,xxx")
wc_bhn = sum_normalize2(cgt.exp(tmp_bhn))
# Interpolation
g_bh1 = g_bh[:, :, None]
wg_bhn = cgt.broadcast("*", wprev_bhn, (1 - g_bh1), "xxx,xx1") \
+ cgt.broadcast("*", wc_bhn, g_bh1, "xxx,xx1")
# Shift
wtil_bhn = circ_conv_1d(wg_bhn, s_bh3, axis=2)
# Sharpening
wfin_bhn = sum_normalize2(
cgt.broadcast("**", wtil_bhn, gamma_bh.reshape([opt.b, 2 * opt.h, 1]),
"xxx,xx1"))
b, h, n = opt.b, 2 * opt.h, opt.n
assert infer_shape(wtil_bhn) == (b, h, n)
assert infer_shape(gamma_bh) == (b, h)
assert infer_shape(gamma_bh[:, :, None]) == (b, h, 1)
return wfin_bhn
def ntm_address(opt, wprev_bhn, M_bnm, k_bhm, beta_bh, g_bh, s_bh3, gamma_bh):
# Content addressing
# Cosine similarity
# take inner product along memory axis k * M
numer_bhn = cgt.einsum("bhm,bnm->bhn", k_bhm, M_bnm)
# compute denominator |k| * |m|
denom_bhn = cgt.broadcast("*",
cgt.norm(k_bhm, axis=2, keepdims=True), # -> shape bh1
cgt.norm(M_bnm, axis=2, keepdims=True).transpose([0,2,1]), # -> bn1 -> b1n
"xx1,x1x"
)
csim_bhn = numer_bhn / denom_bhn
assert infer_shape(csim_bhn) == (opt.b, 2*opt.h, opt.n)
# scale by beta
tmp_bhn = cgt.broadcast("*", beta_bh[:,:,None], csim_bhn, "xx1,xxx")
wc_bhn = sum_normalize2(cgt.exp( tmp_bhn ))
# Interpolation
g_bh1 = g_bh[:,:,None]
wg_bhn = cgt.broadcast("*", wprev_bhn, (1 - g_bh1), "xxx,xx1") \
+ cgt.broadcast("*", wc_bhn, g_bh1, "xxx,xx1")
# Shift
wtil_bhn = circ_conv_1d(wg_bhn, s_bh3, axis=2)
# Sharpening
wfin_bhn = sum_normalize2(cgt.broadcast("**", wtil_bhn, gamma_bh.reshape([opt.b,2*opt.h,1]), "xxx,xx1"))
b,h,n = opt.b, 2*opt.h, opt.n
assert infer_shape(wtil_bhn) == (b,h,n)
assert infer_shape(gamma_bh) == (b,h)
assert infer_shape(gamma_bh[:,:,None]) == (b,h,1)
return wfin_bhn
def test_einsum():
x = cgt.tensor3()
y = cgt.tensor3()
sizes = {'i': 2, 'j': 3, 'k': 5, 'l': 7}
xaxes = 'ijk'
yaxes = 'ikl'
zaxes = 'ijl'
for i in xrange(10):
xperm = xaxes
(yperm,
zperm) = permaxes = [[chars[i] for i in np.random.permutation(3)]
for chars in [yaxes, zaxes]]
desc = "%s,%s->%s" % tuple("".join(chars)
for chars in [xperm] + permaxes)
z = cgt.einsum(desc, x, y)
xval = nr.randn(*(sizes[c] for c in xperm))
yval = nr.randn(*(sizes[c] for c in yperm))
np.testing.assert_allclose(cgt.numeric_eval(z, {
x: xval,
y: yval
}),
np.einsum(desc, xval, yval),
atol={
"single": 1e-3,
"double": 1e-6
}[cgt.get_precision()])
def conv2d_fft(x_BKRC, f_LKrc, subsample, pad):
# TODO add shape assertion
f_LKrc = cgt.flip(f_LKrc, [2,3])
padnrows = size(x_BKRC, 2) + size(f_LKrc, 2) - 1
padncols = size(x_BKRC, 3) + size(f_LKrc, 3) - 1
tx = cgt.rfft(x_BKRC, (padnrows,padncols), (2,3))
tf = cgt.rfft(f_LKrc, (padnrows,padncols), (2,3))
out = cgt.irfft( cgt.einsum("BKrc,LKrc->BLrc",tx, tf), (2,3))
out = out[:,:,pad[0]:(padnrows-pad[0]):subsample[0],pad[1]:(padncols-pad[1]):subsample[1]] #pylint: disable=E1127
return out
def conv2d_fft(x_BKRC, f_LKrc, subsample, pad):
# TODO add shape assertion
f_LKrc = cgt.flip(f_LKrc, [2,3])
padnrows = size(x_BKRC, 2) + size(f_LKrc, 2) - 1
padncols = size(x_BKRC, 3) + size(f_LKrc, 3) - 1
tx = cgt.rfft(x_BKRC, (padnrows,padncols), (2,3))
tf = cgt.rfft(f_LKrc, (padnrows,padncols), (2,3))
out = cgt.irfft( cgt.einsum("BKrc,LKrc->BLrc",tx, tf), (2,3))
out = out[:,:,pad[0]:(padnrows-pad[0]):subsample[0],pad[1]:(padncols-pad[1]):subsample[1]] #pylint: disable=E1127
return out
def ntm_write(M_bnm, w_bhn, e_bhm, a_bhm):
if False: # Here's the version that's faithful to the paper
# weighted erases bhn1 bh1m
# ideally we wouldn't create this big 4-tensor but this operation
# requires a more general kind of contraction than is provided by einsum
we_bhmn = cgt.broadcast("*", w_bhn[:,:,:,None], e_bhm[:,:,None,:], "xxx1,xx1x")
# take produce of erasing factors
mult_bmn = (1 - we_bhmn).prod(axis=1)
M_bnm = M_bnm * mult_bmn # Equation 3 http://arxiv.org/pdf/1410.5401v2.pdf
else: # This version just does a regular contraction
erase_bnm = cgt.einsum( "bhn,bhm->bnm", w_bhn, e_bhm)
M_bnm = M_bnm*(1-erase_bnm)
# Now do the same thing with adds
# But now it's just a regular contraction since we are adding rather than taking product
add_bnm = cgt.einsum( "bhn,bhm->bnm", w_bhn, a_bhm)
M_bnm = M_bnm + add_bnm
return M_bnm
def ntm_write(M_bnm, w_bhn, e_bhm, a_bhm):
if False: # Here's the version that's faithful to the paper
# weighted erases bhn1 bh1m
# ideally we wouldn't create this big 4-tensor but this operation
# requires a more general kind of contraction than is provided by einsum
we_bhmn = cgt.broadcast("*", w_bhn[:,:,:,None], e_bhm[:,:,None,:], "xxx1,xx1x")
# take produce of erasing factors
mult_bmn = (1 - we_bhmn).prod(axis=1)
M_bnm = M_bnm * mult_bmn # Equation 3 http://arxiv.org/pdf/1410.5401v2.pdf
else: # This version just does a regular contraction
erase_bnm = cgt.einsum( "bhn,bhm->bnm", w_bhn, e_bhm)
M_bnm = M_bnm*(1-erase_bnm)
# Now do the same thing with adds
# But now it's just a regular contraction since we are adding rather than taking product
add_bnm = cgt.einsum( "bhn,bhm->bnm", w_bhn, a_bhm)
M_bnm = M_bnm + add_bnm
return M_bnm
def test_einsum():
x = cgt.tensor3()
y = cgt.tensor3()
sizes = {"i": 2, "j": 3, "k": 5, "l": 7}
xaxes = "ijk"
yaxes = "ikl"
zaxes = "ijl"
for i in xrange(10):
xperm = xaxes
(yperm, zperm) = permaxes = [[chars[i] for i in np.random.permutation(3)] for chars in [yaxes, zaxes]]
desc = "%s,%s->%s" % tuple("".join(chars) for chars in [xperm] + permaxes)
z = cgt.einsum(desc, x, y)
xval = nr.randn(*(sizes[c] for c in xperm))
yval = nr.randn(*(sizes[c] for c in yperm))
np.testing.assert_allclose(
cgt.numeric_eval(z, {x: xval, y: yval}),
np.einsum(desc, xval, yval),
atol={"single": 1e-3, "double": 1e-6}[cgt.get_precision()],
)
def test_einsum():
cgt.reset_config()
cgt.set_precision("double")
x = cgt.tensor3()
y = cgt.tensor3()
sizes = {'i':2,'j':3,'k':5,'l':7}
xaxes = 'ijk'
yaxes = 'ikl'
zaxes = 'ijl'
for i in xrange(10):
xperm = xaxes
(yperm,zperm) = permaxes = [[chars[i] for i in np.random.permutation(3)] for chars in [yaxes,zaxes]]
desc = "%s,%s->%s"%tuple("".join(chars) for chars in [xperm] + permaxes)
z = cgt.einsum(desc, x, y)
xval = nr.randn(*(sizes[c] for c in xperm))
yval = nr.randn(*(sizes[c] for c in yperm))
np.testing.assert_allclose(
cgt.numeric_eval(z, {x : xval, y : yval}),
np.einsum(desc, xval, yval))
def ntm_read(M_bnm, w_bhn):
r_bhm = cgt.einsum('bhn,bnm->bhm', w_bhn, M_bnm)
return r_bhm
def ntm_read(M_bnm, w_bhn):
r_bhm = cgt.einsum('bhn,bnm->bhm', w_bhn, M_bnm)
return r_bhm
