download - 在 Google Colaboratory 上保存或下载 plotly iplot 图像

Question

我一直在尝试下载在 google colaboratory 上使用 plotly 创建的图。到目前为止，这是我尝试过的:

我试过改变

files.download('foo.svg')

到

files.download('foo')

我仍然没有得到任何结果。我导航到 Google colab 上的文件，但那里没有任何显示

import numpy as np 
import pandas as pd
from plotly.offline import iplot
import plotly.graph_objs as go
from google.colab import files

def enable_plotly_in_cell():
  import IPython
  from plotly.offline import init_notebook_mode
  display(IPython.core.display.HTML('''<script src="/static/components/requirejs/require.js"></script>'''))
  init_notebook_mode(connected=False)

#this actually shows the plot 
enable_plotly_in_cell()

N = 500
x = np.linspace(0, 1, N)
y = np.random.randn(N)
df = pd.DataFrame({'x': x, 'y': y})
df.head()

data = [
    go.Scatter(
        x=df['x'], # assign x as the dataframe column 'x'
        y=df['y']
    )
]

iplot(data,image = 'svg', filename = 'foo')

files.download('foo.svg')

这是我得到的错误:

OSErrorTraceback (most recent call last)
<ipython-input-18-31523eb02a59> in <module>()
     29 iplot(data,image = 'svg', filename = 'foo')
     30 
---> 31 files.download('foo.svg')
     32 

/usr/local/lib/python2.7/dist-packages/google/colab/files.pyc in download(filename)
    140     msg = 'Cannot find file: {}'.format(filename)
    141     if _six.PY2:
--> 142       raise OSError(msg)
    143     else:
    144       raise FileNotFoundError(msg)  # pylint: disable=undefined-variable

OSError: Cannot find file: foo.svg

Answer 1

要从 Plotly 图形中保存矢量或光栅图像(例如 SVG 或 PNG)，您需要拥有 Kaleido (首选)或 Orca (legacy) 安装，这实际上可以在 Colab 中使用以下命令:
万花筒:

!pip install kaleido

逆戟鲸:

!pip install plotly>=4.0.0
!wget https://github.com/plotly/orca/releases/download/v1.2.1/orca-1.2.1-x86_64.AppImage -O /usr/local/bin/orca
!chmod +x /usr/local/bin/orca
!apt-get install xvfb libgtk2.0-0 libgconf-2-4

完成上述任一操作后，您可以使用以下代码制作、显示和导出图形(使用 plotly 版本 4):

import plotly.graph_objects as go
fig = go.Figure( go.Scatter(x=[1,2,3], y=[1,3,2] ) )
fig.show()
fig.write_image("image.svg")
fig.write_image("image.png")

然后可以使用以下命令下载文件:

from google.colab import files
files.download('image.svg')
files.download('image.png')