Repository: zeppelin Updated Branches: refs/heads/master 100b97821 -> 8b40268d1
ZEPPELIN-1318 - Add support for matplotlib displaying png images in python interpreter ### What is this PR for? This PR adds support for plotting png images using the matplotlib helper function within a python interpreter (eg `z.show()`). The primary motivation for this is due to the overhead incurred from svg images, which can lag the notebooks if multiple, complicated images are generated (for example, multiple filled contour plots). png images are more lightweight, but of course come at a cost of image quality due to them being raster rather than vector like svg. The support for png images is incorporated through the use of a new optional argument to `z.show` called `fmt` which can be one of `'svg'` or `'png'`. The same code that is currently used in show is used for svg images while the code for png images relies on converting the image directly to a byte array and then entering the decoded byte string directly into an HTML image tag. Currently `fmt` defaults to `'png'` but I think we should consider discussing the pros and cons of each option in this PR. ### What type of PR is it? Improvement ### What is the Jira issue? [ZEPPELIN-1318](https://issues.apache.org/jira/browse/ZEPPELIN-1318) ### How should this be tested? In a notebook cell, enter: ```python %python import matplotlib.pyplot as plt import numpy as np plt.figure() plt.plot(np.arange(10)) z.show(plt, fmt=fmt) ``` Where `fmt` may be one of `'svg'` or `'png'`, and any other input should result in a `ValueError`. I would also recommend testing the example in the screenshot below. ### Screenshots (if appropriate)  ### Questions: * Does the licenses files need update? No * Is there breaking changes for older versions? No * Does this needs documentation? Yes (if the changes to the `help()` docstring are not sufficient) Author: Alex Goodman <[email protected]> Closes #1329 from agoodm/ZEPPELIN-1318 and squashes the following commits: 2e9ce4c [Alex Goodman] Update python.md 1efa0c9 [Alex Goodman] ZEPPELIN-1318 - Add support for png images in z.show() Project: http://git-wip-us.apache.org/repos/asf/zeppelin/repo Commit: http://git-wip-us.apache.org/repos/asf/zeppelin/commit/8b40268d Tree: http://git-wip-us.apache.org/repos/asf/zeppelin/tree/8b40268d Diff: http://git-wip-us.apache.org/repos/asf/zeppelin/diff/8b40268d Branch: refs/heads/master Commit: 8b40268d1665f9b5238fb1ee15846f25de8d1634 Parents: 100b978 Author: Alex Goodman <[email protected]> Authored: Fri Aug 12 21:42:48 2016 -0700 Committer: Alexander Bezzubov <[email protected]> Committed: Sun Aug 14 11:28:38 2016 +0900 ---------------------------------------------------------------------- docs/interpreter/python.md | 6 +++--- python/src/main/resources/bootstrap.py | 24 ++++++++++++++++++------ 2 files changed, 21 insertions(+), 9 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/zeppelin/blob/8b40268d/docs/interpreter/python.md ---------------------------------------------------------------------- diff --git a/docs/interpreter/python.md b/docs/interpreter/python.md index dc10a75..4aa3468 100644 --- a/docs/interpreter/python.md +++ b/docs/interpreter/python.md @@ -87,7 +87,7 @@ print("".join(z.checkbox("f3", [("o1","1"), ("o2","2")],["1"]))) ## Matplotlib integration The python interpreter can display matplotlib graph with the function `z.show()`. - You need to have matplotlib module installed and a XServer running to use this functionality ! + You need to have matplotlib module installed and a XServer running to use this functionality! ```python %python @@ -97,12 +97,12 @@ plt.figure() z.show(plt) plt.close() ``` -z.show function can take optional parameters to adapt graph width and height +The `z.show()` function can take optional parameters to adapt graph dimensions (width and height) as well as output format (png or optionally svg). ```python %python z.show(plt, width='50px') -z.show(plt, height='150px') +z.show(plt, height='150px', fmt='svg') ``` <img class="img-responsive" src="../assets/themes/zeppelin/img/docs-img/pythonMatplotlib.png" /> http://git-wip-us.apache.org/repos/asf/zeppelin/blob/8b40268d/python/src/main/resources/bootstrap.py ---------------------------------------------------------------------- diff --git a/python/src/main/resources/bootstrap.py b/python/src/main/resources/bootstrap.py index 889b456..9e93839 100644 --- a/python/src/main/resources/bootstrap.py +++ b/python/src/main/resources/bootstrap.py @@ -19,6 +19,7 @@ # Remove interactive mode displayhook import sys import signal +import base64 try: import StringIO as io @@ -69,10 +70,10 @@ def help(): plt.close() </pre> <div><br/> z.show function can take optional parameters - to adapt graph width and height</div> + to adapt graph dimensions (width and height) and format (png or svg)</div> <div><b>example </b>: <pre>z.show(plt,width='50px - z.show(plt,height='150px') </pre></div> + z.show(plt,height='150px', fmt='svg') </pre></div> <h3>Pandas DataFrame</h3> <div> You need to have Pandas module installed @@ -163,13 +164,24 @@ class PyZeppelinContext(object): #) body_buf.close(); header_buf.close() - def show_matplotlib(self, p, width="100%", height="100%", **kwargs): + def show_matplotlib(self, p, width="100%", height="100%", + fmt='png', **kwargs): """Matplotlib show function """ img = io.StringIO() - p.savefig(img, format="svg") - html = "%html <div style='width:{width};height:{height}'>{image}<div>" - print(html.format(width=width, height=height, image=img.getvalue())) + if fmt == 'png': + p.savefig(img, format=fmt) + html = "%html <img src={img} width={width}, height={height}>" + img_str = "data:image/png;base64," + img_str += base64.b64encode(img.getvalue().strip()) + elif fmt == 'svg': + p.savefig(img, format=fmt) + html = "%html <div style='width:{width};height:{height}'>{img}<div>" + img_str = img.getvalue() + else: + raise ValueError("fmt must be 'png' or 'svg'") + + print(html.format(width=width, height=height, img=img_str)) img.close()
