In [1]:

    

import numpy as np


    

In [2]:

    

a = np.array([1, 2, 3])
print(a)
print(a.dtype)


    

    




[1 2 3]
int64

In [3]:

    

a_float = a.astype(np.float32)
print(a_float)
print(a_float.dtype)


    

    




[1. 2. 3.]
float32

In [4]:

    

print(a)
print(a.dtype)


    

    




[1 2 3]
int64

In [5]:

    

a_float = a.astype(float)
print(a_float)
print(a_float.dtype)


    

    




[1. 2. 3.]
float64

In [6]:

    

a_str = a.astype('str')
print(a_str)
print(a_str.dtype)


    

    




['1' '2' '3']
<U21

In [7]:

    

a_int = a.astype('int32')
print(a_int)
print(a_int.dtype)


    

    




[1 2 3]
int32

In [8]:

    

a = np.arange(50).reshape((5, 10)) / 10 - 2
print(a)
print(a.dtype)


    

    




[[-2.  -1.9 -1.8 -1.7 -1.6 -1.5 -1.4 -1.3 -1.2 -1.1]
 [-1.  -0.9 -0.8 -0.7 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1]
 [ 0.   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9]
 [ 1.   1.1  1.2  1.3  1.4  1.5  1.6  1.7  1.8  1.9]
 [ 2.   2.1  2.2  2.3  2.4  2.5  2.6  2.7  2.8  2.9]]
float64

In [9]:

    

a_int = a.astype('int64')
print(a_int)
print(a_int.dtype)


    

    




[[-2 -1 -1 -1 -1 -1 -1 -1 -1 -1]
 [-1  0  0  0  0  0  0  0  0  0]
 [ 0  0  0  0  0  0  0  0  0  0]
 [ 1  1  1  1  1  1  1  1  1  1]
 [ 2  2  2  2  2  2  2  2  2  2]]
int64

In [10]:

    

print(np.round(a).astype(int))


    

    




[[-2 -2 -2 -2 -2 -2 -1 -1 -1 -1]
 [-1 -1 -1 -1 -1  0  0  0  0  0]
 [ 0  0  0  0  0  0  1  1  1  1]
 [ 1  1  1  1  1  2  2  2  2  2]
 [ 2  2  2  2  2  2  3  3  3  3]]

In [11]:

    

my_round_int = lambda x: np.round((x * 2 + 1) // 2)


    

In [12]:

    

print(my_round_int(a).astype(int))


    

    




[[-2 -2 -2 -2 -2 -1 -1 -1 -1 -1]
 [-1 -1 -1 -1 -1  0  0  0  0  0]
 [ 0  0  0  0  0  1  1  1  1  1]
 [ 1  1  1  1  1  2  2  2  2  2]
 [ 2  2  2  2  2  3  3  3  3  3]]

In [13]:

    

def my_round(x, digit=0):
    p = 10 ** digit
    s = np.copysign(1, x)
    return (s * x * p * 2 + 1) // 2 / p * s


    

In [14]:

    

print(my_round(a).astype(int))


    

    




[[-2 -2 -2 -2 -2 -2 -1 -1 -1 -1]
 [-1 -1 -1 -1 -1 -1  0  0  0  0]
 [ 0  0  0  0  0  1  1  1  1  1]
 [ 1  1  1  1  1  2  2  2  2  2]
 [ 2  2  2  2  2  3  3  3  3  3]]