Python rounding values not working with Numpy condition produce TypeError: '<' not supported between instances of 'list' and 'float

Question

我有这样的情况，当数组中的某个阈值 (22.0) 舍入为 0 时，numpy 条件不起作用。 numpy 条件 rainB[np.where(rainB<threshold)]=0.0 的第二个选项也不起作用。结果显示;TypeError: '<' not supported between instances of 'list' and 'float'。有人有想法吗？谢谢

tempA=[183.650,185.050,185.250,188.550]    
rainA=[41.416,16.597,20.212,30.029]    
threshold=22.0
temp_new=[183.110,187.20,184.30,186.0]

rainB=[]
for x in temp_new:
    if x <=185.0:
        rain1 = np.interp(x, tempA, rainA)
    else:
        rain1=0.2*x+0.7
    
    rainB.append(rain1)

    rainB[rainB < threshold] = 0.0
    ##rainB[np.where(rainB<threshold)]=0.0

Answer 1

列表理解可以在这里工作：

 rainB = [0 if x < threshold else x for x in rainB]

见if/else in a list comprehension。

Answer 2

问题是 rainB 是一个列表而不是一个 numpy 数组，但您正试图将它与 numpy 工具一起使用。您可以使用 numpy 重写整个代码，如下所示：

import numpy as np

tempA = [183.650, 185.050, 185.250, 188.550]
rainA = [41.416, 16.597, 20.212, 30.029]
threshold = 22.0
temp_new = [183.110, 187.20, 184.30, 186.0]

arr = np.array(temp_new)
rainB = np.where(arr <= 185, np.interp(temp_new, tempA, rainA), 0.2 * arr + 0.7)
rainB[rainB < threshold] = 0.0

print(rainB)

它给出：

[41.416      38.14       29.89289286 37.9       ]

Python rounding values not working with Numpy condition produce TypeError: '<' not supported between instances of 'list' and 'float

Python rounding values not working with Numpy condition produce TypeError: '<' not supported between instances of 'list' and 'float

python

rounding

numpy-ndarray