Python|将字符串数组转换为浮点数组的方法

有时在竞争激烈的编码环境中，我们得到一些其他数据类型的输入，我们需要将它们转换为其他形式。这个问题与我们有一个字符串形式的输入，我们需要将其转换为浮点数相同。
让我们讨论几种将字符串数组转换为浮点数组的方法。
方法#1：使用 astype

Python3

# Python code to demonstrate converting
# array of strings to array of floats
# using astype
 
import numpy as np
 
# initialising array
ini_array = np.array(["1.1", "1.5", "2.7", "8.9"])
 
# printing initial array
print ("initial array", str(ini_array))
 
# converting to array of floats
# using np.astype
res = ini_array.astype(np.float)
 
# printing final result
print ("final array", str(res))

输出：

initial array ['1.1' '1.5' '2.7' '8.9']
final array [ 1.1  1.5  2.7  8.9]

方法 #2：使用 np.fromstring

Python3

# Python code to demonstrate converting
# array of strings to array of floats
# using fromstring
 
import numpy as np
 
# initialising array
ini_array = np.array(["1.1", "1.5", "2.7", "8.9"])
 
# printing initial array
print ("initial array", str(ini_array))
 
# converting to array of floats
# using np.fromstring
ini_array = ', '.join(ini_array)
ini_array = np.fromstring(ini_array, dtype = np.float,
                                           sep =', ' )
 
# printing final result
print ("final array", str(ini_array))

输出：

initial array ['1.1' '1.5' '2.7' '8.9']
final array [ 1.1  1.5  2.7  8.9]

方法 #3：使用 np.asarray() 和类型

Python3

# Python code to demonstrate
# converting array of strings to array of floats
# using asarray
 
import numpy as np
 
# initialising array
ini_array = np.array(["1.1", "1.5", "2.7", "8.9"])
 
# printing initial array
print ("initial array", str(ini_array))
 
# converting to array of floats
# using np.asarray
final_array = b = np.asarray(ini_array,
        dtype = np.float64, order ='C')
 
# printing final result
print ("final array", str(final_array))

输出：

initial array ['1.1' '1.5' '2.7' '8.9']
final array [ 1.1  1.5  2.7  8.9]