python 3 pandas 和 seaborn 挣扎使用 swarmplot - multiIndex

Question

我正在努力让 swarmplot 与 pandas 一起工作。我有一个名为 SIAggs 的 3d numpy array，我使用 pandas 将其切片，如下所示:

   rand_center = {('Random_dist'):SIAggs[:,:,1], ('Center_distance'):SIAggs[:,:,0]}

for key, value in rand_center.items():
    rand_center[key] = pd.DataFrame(value)

sizes = {}
for i in range(size_iterations):
    sizes.update({ (str(i+1)) : SIAggs[i,:,:] })
for key, value in sizes.items():
    sizes[key] = pd.DataFrame(value)

df = pd.concat(sizes, rand_center, names = ['sizes', 'distance_measure'])
df.stack()

当我打印 DataFrame 时，它给我:

sizes                  1              2              3       
distance_measure       0      1       0      1       0      1
0                -2.1881  1.262 -2.7001  1.493 -2.1381  1.626
1                -2.3671  1.699 -2.4431  1.208 -2.4571  1.186
2                -2.3071  0.716 -2.2841  1.122 -2.2441  1.396
3                -2.2521  0.967 -1.9451  1.496 -2.5261  1.690
4                -2.4651  1.800 -2.3421  1.500 -2.3571  0.985
5                -2.2011  1.409 -1.9921  0.160 -2.3701  1.114
6                -2.6911  0.915 -3.3301  1.510 -2.2561  1.676
7                -2.5751  1.128 -1.9931  0.941 -2.4411  1.605
8                -2.5321  1.651 -2.4751  1.145 -3.3541  1.228
9                -1.9741  0.886 -2.6671  1.196 -2.4581  1.321

这似乎是对的。

然后，当我尝试用 swarmplot 绘制它时，我想要一个 Series(按我的 sizes 类别)配对(色调差异使用 distance_measure) - 基本上只使用 seaborn website 中的第 5 个示例

ax = sns.swarmplot(x = "sizes", hue = "distance_measure", data = df, split=True)
plt.show()

出现错误:

    ax = sns.swarmplot(x = "sizes", hue = "distance_measure", data = df, split=True)
  File "/Users/scottjg/anaconda/lib/python3.5/site-packages/seaborn/categorical.py", line 2679, in swarmplot
    split, orient, color, palette)
  File "/Users/scottjg/anaconda/lib/python3.5/site-packages/seaborn/categorical.py", line 1179, in __init__
    self.establish_variables(x, y, hue, data, orient, order, hue_order)
  File "/Users/scottjg/anaconda/lib/python3.5/site-packages/seaborn/categorical.py", line 147, in establish_variables
    raise ValueError(err)
ValueError: Could not interpret input 'sizes'

如有任何帮助，我们将不胜感激。我似乎无法与 pandas/seaborn 交 friend ，但我想交 friend !

Answer 1

这里尝试生成您似乎正在寻找的图表，从您的示例数据开始:

df = pd.read_csv('swarm.csv', header=[0, 1], tupleize_cols=True, index_col=None)
cols = ['sizes', 'distance_measure']
df.columns = pd.MultiIndex.from_tuples(df.columns, names=cols)

sizes                  1              2
distance_measure       0      1       0
0                -2.1881  1.262 -2.7001
1                -2.3671  1.699 -2.4431
2                -2.3071  0.716 -2.2841
3                -2.2521  0.967 -1.9451
4                -2.4651  1.800 -2.3421

用于 seaborns 演示的样本数据在不同的列中有变量，而不是使用 MultiIndex，所以我相应地进行转换:

df = df.stack(cols).reset_index(cols).rename(columns={0: 'value'})
df.info()

Int64Index: 30 entries, 0 to 9
Data columns (total 3 columns):
sizes               30 non-null object
distance_measure    30 non-null object
value               30 non-null float64

df.head()

  sizes distance_measure   value
0     1                0 -2.1881
0     1                1  1.2620
0     2                0 -2.7001
1     1                0 -2.3671
1     1                1  1.6990

然后，下面的代码生成类似于示例 #5 的内容:

ax = sns.swarmplot(x="sizes", y='value', hue="distance_measure", data=df, split=True)
plt.show()