Repository: vega/altair

Issue:
savechart doc fix
`savechart` docs note "Supported formats are json, html, png, svg" but the `format` parameters are "the format to write: one of [‘json’, ‘html’, ‘png’, ‘eps’]. If not specified, the format will be determined from the filename.". Presumably eps is out of the picture.


Discussion:
Yes, for some reason my fingers always write eps when my brain is thinking svg. It's happened [before](https://github.com/altair-viz/altair/pull/622/commits/b98fdc7b119584d0599f695d8ad865fa600cd6cb), I'm certain it will happen again :smile:

It needs to be fixed in a few places: https://github.com/altair-viz/altair/search?q=eps&type=Code

Feel free to send a PR changing "eps" to "svg", otherwise I can take care of it

Resolving patch:
diff --git a/altair/utils/save.py b/altair/utils/save.py
--- a/altair/utils/save.py
+++ b/altair/utils/save.py
@@ -21,7 +21,7 @@ def save(chart, fp, vega_version, vegaembed_version,
     fp : string filename or file-like object
         file in which to write the chart.
     format : string (optional)
-        the format to write: one of ['json', 'html', 'png', 'eps'].
+        the format to write: one of ['json', 'html', 'png', 'svg'].
         If not specified, the format will be determined from the filename.
     mode : string (optional)
         Either 'vega' or 'vegalite'. If not specified, then infer the mode from
@@ -51,7 +51,7 @@ def save(chart, fp, vega_version, vegaembed_version,
             format = fp.split('.')[-1]
         else:
             raise ValueError("must specify file format: "
-                             "['png', 'eps', 'html', 'json']")
+                             "['png', 'svg', 'html', 'json']")
 
     spec = chart.to_dict()
 
diff --git a/altair/vegalite/v1/api.py b/altair/vegalite/v1/api.py
--- a/altair/vegalite/v1/api.py
+++ b/altair/vegalite/v1/api.py
@@ -108,7 +108,7 @@ def savechart(self, fp, format=None, **kwargs):
         fp : string filename or file-like object
             file in which to write the chart.
         format : string (optional)
-            the format to write: one of ['json', 'html', 'png', 'eps'].
+            the format to write: one of ['json', 'html', 'png', 'svg'].
             If not specified, the format will be determined from the filename.
         **kwargs :
             Additional keyword arguments are passed to the output method
@@ -130,7 +130,7 @@ def save(self, fp, format=None, **kwargs):
         fp : string filename or file-like object
             file in which to write the chart.
         format : string (optional)
-            the format to write: one of ['json', 'html', 'png', 'eps'].
+            the format to write: one of ['json', 'html', 'png', 'svg'].
             If not specified, the format will be determined from the filename.
         **kwargs :
             Additional keyword arguments are passed to the output method
diff --git a/altair/vegalite/v2/api.py b/altair/vegalite/v2/api.py
--- a/altair/vegalite/v2/api.py
+++ b/altair/vegalite/v2/api.py
@@ -361,7 +361,7 @@ def savechart(self, fp, format=None, **kwargs):
         fp : string filename or file-like object
             file in which to write the chart.
         format : string (optional)
-            the format to write: one of ['json', 'html', 'png', 'eps'].
+            the format to write: one of ['json', 'html', 'png', 'svg'].
             If not specified, the format will be determined from the filename.
         **kwargs :
             Additional keyword arguments are passed to the output method
@@ -383,7 +383,7 @@ def save(self, fp, format=None, **kwargs):
         fp : string filename or file-like object
             file in which to write the chart.
         format : string (optional)
-            the format to write: one of ['json', 'html', 'png', 'eps'].
+            the format to write: one of ['json', 'html', 'png', 'svg'].
             If not specified, the format will be determined from the filename.
         **kwargs :
             Additional keyword arguments are passed to the output method


Test patch: