In [1]:

    

import numpy as np


    

In [2]:

    

print(np.sign(100))


    

    




1

In [3]:

    

print(np.sign(-100))


    

    




-1

In [4]:

    

print(type(np.sign(100)))


    

    




<class 'numpy.int64'>

In [5]:

    

print(np.sign(1.23))


    

    




1.0

In [6]:

    

print(np.sign(-1.23))


    

    




-1.0

In [7]:

    

print(type(np.sign(1.23)))


    

    




<class 'numpy.float64'>

In [8]:

    

print(np.sign(0))


    

    




0

In [9]:

    

print(np.sign(0.0))


    

    




0.0

In [10]:

    

print(np.sign(-0.0))


    

    




0.0

In [11]:

    

print(np.sign(float('nan')))


    

    




nan

In [12]:

    

print(np.sign(float('-nan')))


    

    




nan

In [13]:

    

print(100 > 0)


    

    




True

In [14]:

    

print(True - False)


    

    




1

In [15]:

    

print(False - True)


    

    




-1

In [16]:

    

print(False - False)


    

    




0

In [17]:

    

def my_sign(x):
    return (x > 0) - (x < 0)


    

In [18]:

    

print(my_sign(100))


    

    




1

In [19]:

    

print(my_sign(-100))


    

    




-1

In [20]:

    

print(type(my_sign(100)))


    

    




<class 'int'>

In [21]:

    

print(my_sign(1.23))


    

    




1

In [22]:

    

print(my_sign(-1.23))


    

    




-1

In [23]:

    

print(type(my_sign(-1.23)))


    

    




<class 'int'>

In [24]:

    

print(my_sign(0))


    

    




0

In [25]:

    

print(my_sign(0.0))


    

    




0

In [26]:

    

print(my_sign(-0.0))


    

    




0

In [27]:

    

print(my_sign(float('nan')))


    

    




0

In [28]:

    

print(my_sign(float('-nan')))


    

    




0

In [29]:

    

# print(my_sign(3 + 4j))
# TypeError: '>' not supported between instances of 'complex' and 'int'


    

In [30]:

    

def my_sign_with_abs(x):
    return 0.0 if abs(x) == 0 else x / abs(x)


    

In [31]:

    

print(my_sign_with_abs(100))


    

    




1.0

In [32]:

    

print(my_sign_with_abs(-100))


    

    




-1.0

In [33]:

    

print(type(my_sign_with_abs(100)))


    

    




<class 'float'>

In [34]:

    

print(my_sign_with_abs(1.23))


    

    




1.0

In [35]:

    

print(my_sign_with_abs(-1.23))


    

    




-1.0

In [36]:

    

print(type(my_sign_with_abs(1.23)))


    

    




<class 'float'>

In [37]:

    

print(my_sign_with_abs(0))


    

    




0.0

In [38]:

    

print(my_sign_with_abs(0.0))


    

    




0.0

In [39]:

    

print(my_sign_with_abs(-0.0))


    

    




0.0

In [40]:

    

print(my_sign_with_abs(float('nan')))


    

    




nan

In [41]:

    

print(my_sign_with_abs(float('-nan')))


    

    




nan

In [42]:

    

print(abs(3 + 4j))


    

    




5.0

In [43]:

    

print(my_sign_with_abs(3 + 4j))


    

    




(0.6+0.8j)