""" move step_size in the direction from v """
return [v_i + step_size * direction_i
for v_i, direction_i in zip(v, direction)]
def sum_of_squares_gradient(v):
return [2 * v_i for v_i in v]
# pick a random starting point
v = [random.randint(-10, 10) for i in range(3)]
tolerance = 0.0000001
while True:
gradient = sum_of_squares_gradient(v) # compute the gradient at v
next_v = step(v, gradient, -0.01) # take a negative gradient step
if la.distance(next_v, v) < tolerance:
break
v = next_v # continue if we're not
print(v)
def safe(f):
""" return a new function that's the same as f,
except that it outputs infinity whenever f produces an error """
def safe_f(*args, **kwargs):
try:
return f(*args, **kwargs)
except:
return float('inf') # this means infinity in Python
return safe_f
