In [1]:

    

import numpy as np


    

In [2]:

    

a = np.array([-100, -10, 0, 10, 100])
print(a)


    

    




[-100  -10    0   10  100]

In [3]:

    

print(np.signbit(a))


    

    




[ True  True False False False]

In [4]:

    

print(type(np.signbit(a)))


    

    




<class 'numpy.ndarray'>

In [5]:

    

print(np.signbit(a).dtype)


    

    




bool

In [6]:

    

print(np.signbit(-100))


    

    




True

In [7]:

    

print(a == 0)


    

    




[False False  True False False]

In [8]:

    

print(a > 0)


    

    




[False False False  True  True]

In [9]:

    

print(a >= 0)


    

    




[False False  True  True  True]

In [10]:

    

print(a < 0)


    

    




[ True  True False False False]

In [11]:

    

print(a <= 0)


    

    




[ True  True  True False False]

In [12]:

    

print(np.count_nonzero(np.signbit(a)))


    

    




2

In [13]:

    

print(~np.signbit(a))


    

    




[False False  True  True  True]

In [14]:

    

print(np.count_nonzero(~np.signbit(a)))


    

    




3

In [15]:

    

print(np.count_nonzero(a == 0))


    

    




1

In [16]:

    

print(np.count_nonzero(a < 0))


    

    




2

In [17]:

    

print(np.count_nonzero(a > 0))


    

    




2

In [18]:

    

a_special = np.array([0.0, -0.0, np.inf, -np.inf, np.nan])
print(a_special)


    

    




[  0.  -0.  inf -inf  nan]

In [19]:

    

print(np.signbit(a_special))


    

    




[False  True False  True False]

In [20]:

    

print(a_special == 0)


    

    




[ True  True False False False]

In [21]:

    

print(a_special < 0)


    

    




[False False False  True False]






    




/usr/local/lib/python3.7/site-packages/ipykernel_launcher.py:1: RuntimeWarning: invalid value encountered in less
  """Entry point for launching an IPython kernel.

In [22]:

    

print(a_special > 0)


    

    




[False False  True False False]






    




/usr/local/lib/python3.7/site-packages/ipykernel_launcher.py:1: RuntimeWarning: invalid value encountered in greater
  """Entry point for launching an IPython kernel.

In [23]:

    

a_complex = np.array([3 + 4j, -3 - 4j])
print(a_complex)


    

    




[ 3.+4.j -3.-4.j]

In [24]:

    

# print(np.signbit(a_complex))
# TypeError: ufunc 'signbit' not supported for the input types, and the inputs could not be safely coerced to any supported types according to the casting rule ''safe''


    

In [25]:

    

print(np.abs(a_complex))


    

    




[5. 5.]

In [26]:

    

print(a_complex.real)


    

    




[ 3. -3.]

In [27]:

    

print(a_complex.imag)


    

    




[ 4. -4.]

In [28]:

    

print(np.signbit(a_complex.real))


    

    




[False  True]

In [29]:

    

print(a_complex.real < 0)


    

    




[False  True]