numpy recarray.clip()函数| Python

在 numpy 中，数组可能具有包含字段的数据类型，类似于电子表格中的列。一个例子是[(a, int), (b, float)] ，其中数组中的每个条目都是一对 (int, float)。通常，使用诸如arr['a'] and arr['b']类的字典查找来访问这些属性。

记录数组允许使用arr.a and arr.b作为数组成员访问字段。 numpy.recarray.clip()函数返回一个数组，其值限制为[min, max] 。必须给出 max 或 min 之一。

Syntax : numpy.recarray.clip(min=None, max=None, out=None)

Parameters:
min : Minimum value.
  –> If None, clipping is not performed on lower interval edge. Not more than one of a_min and a_max may be None.
max : Maximum value.
  –> If None, clipping is not performed on upper interval edge. Not more than one of a_min and a_max may be None.
  –> If a_min or a_max are array_like, then the three arrays will be broadcasted to match their shapes.
out : Results will be placed in this array. It may be the input array for in-place clipping. out must be of the right shape to hold the output. Its type is preserved.

Return : [clipped_array, ndarray] An array where values less than minimum are replaced with min, and values greater then maximum with max.

编程需要懂一点英语

代码#1：

# Python program explaining
# numpy.recarray.clip() method 
  
# importing numpy as geek
import numpy as geek
  
# creating input array with 2 different field 
in_arr = geek.array([[(5.0, 2), (3.0, -4), (6.0, 9)], [(9.0, 1), (5.0, 4), (-12.0, -7)]],
        dtype =[('a', float), ('b', int)])
print ("Input array : ", in_arr)
  
# convert it to a record array, using arr.view(np.recarray)
rec_arr = in_arr.view(geek.recarray)
print("Record array of int: ", rec_arr.b)
  
# applying recarray.clip methods to float record array
float_rec_arr = rec_arr.a
print("Record array of float: ", float_rec_arr)
out_arr = (rec_arr.a).clip(min =-1.0, max = 5.0)
print ("Output clipped array : ", out_arr) 
  
# applying recarray.clip methods to int record array
int_rec_arr = rec_arr.b 
print("Record array of int: ", int_rec_arr)
out_arr = int_rec_arr.clip(min = 2, max = 6)
print ("Output clipped array : ", out_arr)

输出：

Input array :  [[(5.0, 2) (3.0, -4) (6.0, 9)]
 [(9.0, 1) (5.0, 4) (-12.0, -7)]]
Record array of int:  [[ 2 -4  9]
 [ 1  4 -7]]
Record array of float:  [[  5.   3.   6.]
 [  9.   5. -12.]]
Output clipped array :  [[ 5.  3.  5.]
 [ 5.  5. -1.]]
Record array of int:  [[ 2 -4  9]
 [ 1  4 -7]]
Output clipped array :  [[2 2 6]
 [2 4 2]]