import numpy as np

def same(x):
    return x

def square(x):
    return np.square(x)

def cube(x):
    return np.power(x,3)

def tanh(x):
    return np.tanh(x)

def negexp(x):
    return np.exp(-np.abs(x))

def cosine(x):
    return np.cos(x)
