def test__dot_var(self):
a = Variable(np.array(1.0))
b = Variable(np.array(1.0))
c = a + b
d = square(c)
actual = get_dot_graph(d)
self.assertIn(f"{id(d.creator)} -> {id(d)}", actual)
self.assertIn(f"{id(c)} -> {id(d.creator)}", actual)
def test_tanh(self):
x = Variable(np.array(1.0))
y = F.tanh(x)
x.name = 'x'
y.name = 'y'
y.backward(create_graph=True)
iters = 0
for i in range(iters):
gx = x.grad
x.cleargrad()
gx.backward(create_graph=True)
gx = x.grad
gx.name = 'gx' + str(iters + 1)
txt = get_dot_graph(gx)
with open('test.dot', 'w') as f:
f.write(txt)
def plot(self, *inputs, to_file='model.png'):
y = self.forward(*inputs)
return utils.get_dot_graph(y, verbose=True, to_file=to_file)
'''
計算グラフの可視化は、次のコマンドで行えます
$ python step22.py | dot -T png -o sample.png
'''
import numpy as np
from dezero import Variable
from dezero.utils import get_dot_graph
def goldstein(x0, x1):
y = (1 + (x0 + x1 + 1)**2 * (19 - 14*x0 + 3*x0**2 - 14*x1 + 6*x0*x1 + 3*x1**2)) *\
(30 + (2*x0 - 3*x1)**2 * (18 - 32*x0 + 12*x0**2 + 48*x1 - 36*x0*x1 + 27*x1**2))
return y
x0 = Variable(np.array(1.0))
x1 = Variable(np.array(1.0))
y = goldstein(x0, x1)
y.backward()
x0.name = 'x0'
x1.name = 'x1'
y.name = 'y'
print(get_dot_graph(y))
def my_sin(x, iters=5):
y = 0
for i in range(iters):
t = (-1)**i * x**(2 * i + 1) / math.factorial(2 * i + 1)
y = y + t
return y
def my_sin(x, threshould=0.0001):
y = 0
for i in range(100000):
t = (-1)**i * x**(2 * i + 1) / math.factorial(2 * i + 1)
y = y + t
if abs(t.data) < threshould:
break
return y
x = Variable(np.array(np.pi / 4))
y = my_sin(x) # , threshould=1e-150)
y.backward()
print('--- approximate sin ---')
print(y.data)
print(x.grad) # 0.7071032148228457
# 可視化 (dotファイルに保存)
x.name = 'x'
y.name = 'y'
dot = get_dot_graph(y)
with open('my_sin.dot', 'w') as o:
o.write(dot)
'''
y=tanh(x)のn階微分
計算グラフの可視化は、次のコマンドで行えます
$ python tanh.py | dot -T png -o sample.png
'''
import numpy as np
from dezero import Variable
from dezero.utils import get_dot_graph
import dezero.functions as F
x = Variable(np.array(1.0))
y = F.tanh(x)
x.name = 'x'
y.name = 'y'
y.backward(create_graph=True)
iters = 3
for i in range(iters):
gx = x.grad
x.cleargrad()
gx.backward(create_graph=True)
gx = x.grad
gx.name = 'gx' + str(iters + 1)
print(get_dot_graph(gx))