如何 plot 列出 python 中字典鍵的值

Question

我有一本包含值列表的字典

df_param = {};
for i in range(0,1000):
  df_param[i]=[[0]]
print(df_param)

df_param={0: [[0], [20], [20], [20], [5], [1], [5]], 1: [[0], [20], [20], [5], [1], [5]], 2: [[0], [20], [20], [5], [5]], 3: [[0], [20], [5], [5]], 4: [[0], [5], [5]], 5: [[0], [5]], 6: [[0]], 7: [[0]], 8: [[0], [20]], 9: [[0]], 10: [[0]]}

我需要 plot x 軸上的每個鍵和 y 軸上的值列表。

這是我的代碼：

for i in range(0,1000):
  for j in range(0,10):
    curr = df1[j][i]['Classifier'][0]
    if(curr=='KNNClassifier'):
      df_param[i].append([df1[j][i]['Classifier'][1]['n_neighbors']])
print(df_param)

import matplotlib.pyplot as plt

import matplotlib.pyplot as plt
for key, values in df_param.items():
    plt.plot(key, values)
plt.show()

我收到以下錯誤。

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-132-176b8a768873> in <module>
      1 import matplotlib.pyplot as plt
      2 for key, values in df_param.items():
----> 3     plt.plot(key, values)
      4 plt.show()

3 frames
/usr/local/lib/python3.7/dist-packages/matplotlib/axes/_base.py in _plot_args(self, tup, kwargs)
    340 
    341         if x.shape[0] != y.shape[0]:
--> 342             raise ValueError(f"x and y must have same first dimension, but "
    343                              f"have shapes {x.shape} and {y.shape}")
    344         if x.ndim > 2 or y.ndim > 2:

ValueError: x and y must have same first dimension, but have shapes (1,) and (7, 1)

Answer 1

如果您的df_param是形式的dict ：

{x0: [[y0_a], [y0_b], ...], x1: [[y1_a], [y1_b], ...], ...}並且您希望對所有(xk, yk_i) ，然后您可以先創建一個包含兩列x和y的適當xy數組：

import numpy as np

xy = np.array([
    (x, y) for x, lst in df_param.items()
    for sublst in lst for y in sublst
])
plt.plot(*xy.T, 'o')