Python中的 numpy.asfarray()

当我们想要将输入转换为浮点类型数组时，使用numpy.asfarray()函数。输入包括标量、列表、元组列表、元组、元组元组、列表元组和 ndarray。

Syntax : numpy.asfarray(arr, dtype=type ‘numpy.float64’)

Parameters :
arr : [array_like] Input data, in any form that can be converted to an float type array. This includes scalar, lists, lists of tuples, tuples, tuples of tuples, tuples of lists and ndarrays.
dtype : Float type code to coerce input array arr. If dtype is one of the ‘int’ dtypes, it is replaced with float64.

Return : [ndarray] The input arr as a float ndarray.

代码 #1：列表到浮点型数组

# Python program explaining
# numpy.asfarray() function
  
import numpy as geek
my_list = [1, 3, 5, 7, 9]
  
print ("Input  list : ", my_list)
   
    
out_arr = geek.asfarray(my_list)
print ("output float type array from input list : ", out_arr) 

输出 ：

Input  list :  [1, 3, 5, 7, 9]
output float type array from input list :  [ 1.  3.  5.  7.  9.]

代码#2：元组到浮点型数组

# Python program explaining
# numpy.asfarray() function
  
import numpy as geek
  
my_tuple = ([1, 3, 9], [8, 2, 6])
   
print ("Input  tuple : ", my_tuple)
    
out_arr = geek.asfarray(my_tuple, dtype ='int8') 
print ("output float type array from input tuple : ", out_arr) 

输出 ：

Input  tuple :  ([1, 3, 9], [8, 2, 6])
output float type array from input tuple :  [[ 1.  3.  9.]
 [ 8.  2.  6.]]

代码#3：标量到浮点型数组

# Python program explaining
# numpy.asfarray() function
  
import numpy as geek
  
my_scalar = 15
   
print ("Input  scalar : ", my_scalar)
    
out_arr = geek.asfarray(my_scalar, dtype ='float') 
print ("output float type array from input scalar : ", out_arr) 

输出 ：

InInput  scalar :  15
output float type array from input scalar :  15.0