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Error saving to SVG

See original GitHub issue

Hi. Using the first example in the docs

from altair import Chart, load_dataset

# load built-in dataset as a pandas DataFrame
cars = load_dataset('cars')

chart = Chart(cars).mark_circle().encode(
    x='Horsepower',
    y='Miles_per_Gallon',
    color='Origin',
)

the following attempt to save to SVG fails

chart.savechart('cars.jpg','jpg')
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/site-packages/IPython/core/interactiveshell.py", line 2881, in run_code
    exec(code_obj, self.user_global_ns, self.user_ns)
  File "<ipython-input-14-b070806b7bcc>", line 1, in <module>
    chart.savechart('cars.jpg','jpg')
  File "/usr/local/lib/python2.7/site-packages/altair/api.py", line 182, in savechart
    supported = _node.SUPPORTED_FILETYPES + ['json', 'html']
NameError: global name '_node' is not defined

and attempting to use vl2svg directly gives the error

vl2svg cars.json cars.jpg
/usr/local/lib/node_modules/vega/build/vega.js:686
  throw Error(message);
  ^

Error: Missing required "filter" parameter: "expr"
    at error (/usr/local/lib/node_modules/vega/build/vega.js:686:9)
    at parseParameter$1 (/usr/local/lib/node_modules/vega/build/vega.js:28796:9)
    at parseParameters (/usr/local/lib/node_modules/vega/build/vega.js:28775:25)
    at parseTransform (/usr/local/lib/node_modules/vega/build/vega.js:28763:35)
    at /usr/local/lib/node_modules/vega/build/vega.js:29639:23
    at Array.forEach (native)
    at parseData$1 (/usr/local/lib/node_modules/vega/build/vega.js:29638:20)
    at /usr/local/lib/node_modules/vega/build/vega.js:30045:5
    at Array.forEach (native)
    at parseSpec (/usr/local/lib/node_modules/vega/build/vega.js:30044:22)

I have installed canvas, vega and vega-lite and altair is the pypi version.

Issue Analytics

State:
Created 7 years ago
Comments:15 (5 by maintainers)

Top GitHub Comments

1reaction

jakevdpcommented, May 17, 2018

This is no longer relevant, because Altair 2 uses selenium rather than node for programmatic export.

1reaction

jakevdpcommented, Sep 27, 2017

For what it’s worth, I can no longer get this to work on any of my machines. I think the NodeJS+shell dependency is something we’re going to have to figure out how to move away from (Bokeh has an interesting approach that we may adopt)