python 中的 numpy.ptp()
numpy.ptp() 函数通过找出给定数字的范围，在统计中发挥重要作用。范围=最大值–最小值。
语法: ndarray.ptp(arr，axis=None，out=None) 参数: arr : 输入数组。 轴:轴，我们希望范围值沿着该轴。否则，它将考虑将 arr 展平(在所有轴上工作)。axis = 0 表示沿列工作，axis = 1 表示沿行工作。 out:【n 数组，可选】我们要放置结果的不同数组。数组必须具有与预期输出相同的维度。 返回:数组的范围(如果轴为无，则为标量值)或具有沿指定轴的值范围的数组。
代码#1:工作
计算机编程语言
# Python Program illustrating
# numpy.ptp() method
import numpy as np
# 1D array
arr = [1, 2, 7, 20, np.nan]
print("arr : ", arr)
print("Range of arr : ", np.ptp(arr))
# 1D array
arr = [1, 2, 7, 10, 16]
print("arr : ", arr)
print("Range of arr : ", np.ptp(arr))
输出:
arr : [1, 2, 7, 20, nan]
Range of arr : nan
arr : [1, 2, 7, 10, 16]
Range of arr : 15
代码#2 :
计算机编程语言
# Python Program illustrating
# numpy.ptp() method
import numpy as np
# 3D array
arr = [[14, 17, 12, 33, 44],
[15, 6, 27, 8, 19],
[23, 2, 54, 1, 4,]]
print("\narr : \n", arr)
# Range of the flattened array
print("\nRange of arr, axis = None : ", np.ptp(arr))
# Range along the first axis
# axis 0 means vertical
print("Range of arr, axis = 0 : ", np.ptp(arr, axis = 0))
# Range along the second axis
# axis 1 means horizontal
print("Min of arr, axis = 1 : ", np.ptp(arr, axis = 1))
输出:
arr :
[[14, 17, 12, 33, 44], [15, 6, 27, 8, 19], [23, 2, 54, 1, 4]]
Range of arr, axis = None : 53
Range of arr, axis = 0 : [ 9 15 42 32 40]
Min of arr, axis = 1 : [32 21 53]
代码#3 :
计算机编程语言
# Python Program illustrating
# numpy.ptp() method
import numpy as np
arr1 = np.arange(5)
print("\nInitial arr1 : ", arr1)
# using out parameter
np.ptp(arr, axis = 0, out = arr1)
print("Changed arr1(having results) : ", arr1)
输出:
Initial arr1 : [0 1 2 3 4]
Changed arr1(having results) : [ 9 15 42 32 40]
