Question

我在熊猫中设置了以下数据。

import numpy as np
import pandas as pd

events = ['event1', 'event2', 'event3', 'event4', 'event5', 'event6']

wells = [np.array([1, 2]), np.array([1, 3]), np.array([1]),
 np.array([4, 5, 6]), np.array([4, 5, 6]), np.array([7, 8])]

traces_per_well = [np.array([24, 24]), np.array([24, 21]), np.array([18]),
 np.array([24, 24, 24]), np.array([24, 21, 24]), np.array([18, 21])]

df = pd.DataFrame({"event_no": events, "well_array": wells,
  "trace_per_well": traces_per_well})

df["total_traces"] = df['trace_per_well'].apply(np.sum)

df['supposed_traces_no'] = df['well_array'].apply(lambda x: len(x)*24)

df['pass'] = df['total_traces'] == df['supposed_traces_no']
print(df)

输出显示在下面：

  event_no well_array trace_per_well  total_traces  supposed_traces_no   pass
0   event1     [1, 2]       [24, 24]            48                  48   True
1   event2     [1, 3]       [24, 21]            45                  48  False
2   event3        [1]           [18]            18                  24  False
3   event4  [4, 5, 6]   [24, 24, 24]            72                  72   True
4   event5  [4, 5, 6]   [24, 21, 24]            69                  72  False
5   event6     [7, 8]       [18, 21]            39                  48  False

我想创建两个新列，其中将不等于24的列trace_per_well中的numpy数组项放在一列中，并将来自列well_array的对应数组元素中的列另一列

结果应如下所示。

  event_no well_array trace_per_well  total_traces  supposed_traces_no   pass wrong_trace_in_well wrong_well
0   event1     [1, 2]       [24, 24]            48                  48   True                 NaN        NaN
1   event2     [1, 3]       [24, 21]            45                  48  False                  21          3
2   event3        [1]           [18]            18                  24  False                  18          1
3   event4  [4, 5, 6]   [24, 24, 24]            72                  72   True                 NaN        NaN
4   event5  [4, 5, 6]   [24, 21, 24]            69                  72  False                  21          5
5   event6     [7, 8]       [18, 21]            39                  48  False            (18, 21)     (7, 8)

非常感谢您的帮助！

Answer 1

我会通过列表理解来做到这一点。单次传递数据即可生成结果，然后将其分配给适当的列。

v = pd.Series(
        [list(zip(*((x, y) for x, y in zip(X, Y) if x != 24))) 
            for X, Y in zip(df['trace_per_well'], df['well_array'])])

df['wrong_trace_in_well'] = v.str[0]
df['wrong_well'] = v.str[-1]

df[['wrong_trace_in_well', 'wrong_well']]

  wrong_trace_in_well wrong_well
0                 NaN        NaN
1               (21,)       (3,)
2               (18,)       (1,)
3                 NaN        NaN
4               (21,)       (5,)
5            (18, 21)     (7, 8)

或者，如果您想多次通过，则

df['wrong_trace_in_well'] = [[x for x in X if x != 24] for X in df['trace_per_well']]
df['wrong_well'] = [
    [y for x, y in zip(X, Y) if x != 24] 
        for X, Y in  zip(df['trace_per_well'], df['well_array'])]

df[['wrong_trace_in_well', 'wrong_well']]

  wrong_trace_in_well wrong_well
0                  []         []
1                [21]        [3]
2                [18]        [1]
3                  []         []
4                [21]        [5]
5            [18, 21]     [7, 8]

根据熊猫另一列中另一个数组中另一个元素的值获取列中数组的元素

1 个答案: