Python | Numpy nan middle()函数
原文:https://www . geeksforgeeks . org/python-numpy-nan median-function/
numpy . NaN middle()函数可以用来计算忽略 NaN 值的数组的中值。如果数组有 NaN 值，我们可以在不影响 NaN 值的情况下求出中值。让我们看看关于 numpy.nanmedian()方法的不同类型的例子。
语法:numpy . nan middle(a，axis=None，out=None，overwrite_input=False，keepdims=) 参数: a:【arr _ like】输入数组 axis: 我们可以用 axis=1 表示行方向，axis=0 表示列方向。 出:输出数组 overwrite_input: 如果为真，则允许使用输入数组 a 的内存进行计算。对中值的调用将修改输入数组。 保持尺寸:如果设置为真，减少的轴将作为尺寸为 1 的尺寸留在结果中。使用此选项，结果将正确地广播到原始 a. 返回:返回 n 数组中的中间值。
示例#1:
蟒蛇 3
# Python code to demonstrate the
# use of numpy.nanmedian
import numpy as np
# create 2d array with nan value.
arr = np.array([[12, 10, 34], [45, 23, np.nan]])
print("Shape of array is", arr.shape)
print("Median of array without using nanmedian function:",
np.median(arr))
print("Using nanmedian function:", np.nanmedian(arr))
输出:
Shape of array is (2, 3)
Median of array without using nanmedian function: nan
Using nanmedian function: 23.0
例 2:
蟒蛇 3
# Python code to demonstrate the
# use of numpy.nanmedian
# with axis
import numpy as np
# create 2d array with nan value.
arr = np.array([[12, 10, 34], [45, 23, np.nan]])
print("Shape of array is", arr.shape)
print("Median of array with axis = 0:",
np.median(arr, axis = 0))
print("Using nanmedian function:",
np.nanmedian(arr, axis = 0))
输出:
Shape of array is (2, 3)
Median of array with axis = 0: [ 28.5 16.5 nan]
Using nanmedian function: [ 28.5 16.5 34\. ]
示例#3:
蟒蛇 3
# Python code to demonstrate the
# use of numpy.nanmedian
# with axis = 1
import numpy as np
# create 2d matrix with nan value
arr = np.array([[12, 10, 34],
[45, 23, np.nan],
[7, 8, np.nan]])
print("Shape of array is", arr.shape)
print("Median of array with axis = 0:",
np.median(arr, axis = 1))
print("Using nanmedian function:",
np.nanmedian(arr, axis = 1))
输出:
Shape of array is (3, 3)
Median of array with axis = 0: [ 12\. nan nan]
Using nanmedian function: [ 12\. 34\. 7.5]
