html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue
https://github.com/pydata/xarray/pull/509#issuecomment-128417092,https://api.github.com/repos/pydata/xarray/issues/509,128417092,MDEyOklzc3VlQ29tbWVudDEyODQxNzA5Mg==,5356122,2015-08-06T15:53:54Z,2015-08-06T15:53:54Z,MEMBER,"Yes, looks good. Merge away!
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-128230468,https://api.github.com/repos/pydata/xarray/issues/509,128230468,MDEyOklzc3VlQ29tbWVudDEyODIzMDQ2OA==,2443309,2015-08-06T04:11:22Z,2015-08-06T04:11:22Z,MEMBER,"@shoyer - have a good time.
@clarkfitzg - I think I've addressed all your comments, including returning a `dict` from `_determine_cmap_params`. If there is nothing else, I'll merge this tomorrow.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-128193197,https://api.github.com/repos/pydata/xarray/issues/509,128193197,MDEyOklzc3VlQ29tbWVudDEyODE5MzE5Nw==,1217238,2015-08-06T00:30:31Z,2015-08-06T00:30:31Z,MEMBER,"@jhamman you should merge this once you and @clarkfitzg are happy. I'm about go offline for 6 days (backpacking in the Olympics).
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-128188132,https://api.github.com/repos/pydata/xarray/issues/509,128188132,MDEyOklzc3VlQ29tbWVudDEyODE4ODEzMg==,5356122,2015-08-06T00:01:02Z,2015-08-06T00:01:02Z,MEMBER,"Nice work @jhamman @shoyer. Tests look pretty thorough and I like all the helper functions.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-128158707,https://api.github.com/repos/pydata/xarray/issues/509,128158707,MDEyOklzc3VlQ29tbWVudDEyODE1ODcwNw==,1217238,2015-08-05T21:45:53Z,2015-08-05T21:45:53Z,MEMBER,"@clarkfitzg any thoughts here?
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-128158577,https://api.github.com/repos/pydata/xarray/issues/509,128158577,MDEyOklzc3VlQ29tbWVudDEyODE1ODU3Nw==,1217238,2015-08-05T21:45:13Z,2015-08-05T21:45:13Z,MEMBER,"These tests look great -- thanks!
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-128091418,https://api.github.com/repos/pydata/xarray/issues/509,128091418,MDEyOklzc3VlQ29tbWVudDEyODA5MTQxOA==,2443309,2015-08-05T17:56:46Z,2015-08-05T17:56:46Z,MEMBER,"@shoyer - I added a bunch of tests this morning and checked off the list of documentation and error handling items. Take another look and let me know if you think we need anymore tests or changes to the docs.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-127673118,https://api.github.com/repos/pydata/xarray/issues/509,127673118,MDEyOklzc3VlQ29tbWVudDEyNzY3MzExOA==,2443309,2015-08-04T16:51:59Z,2015-08-05T17:24:21Z,MEMBER,"This looks good. Thanks for doing that.
> Are there any cases where you would want to set vmin/vmax to something other than the first and last levels?
Yes, but they are rare and you could pass in a custom `norm` in those cases.
> This assuredly still needs more tests -- mostly to verify that every plot types ends up with consistent levels.
I'll think a bit more about how to test these aspects.
---
There are three things left to do here (this has gotten a big bigger than I was expecting):
- [x] Decide what to do with seaborn's handling of `jet`
- [x] Fill in tests
- [x] Add an example in the plot docs
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-127507325,https://api.github.com/repos/pydata/xarray/issues/509,127507325,MDEyOklzc3VlQ29tbWVudDEyNzUwNzMyNQ==,1217238,2015-08-04T07:30:37Z,2015-08-04T07:30:37Z,MEMBER,"Decided to try reorganizing things and got sucked in, so I ended up making a PR to your fork with some tweaks:
https://github.com/jhamman/xray/pull/1
This assuredly still needs more tests -- mostly to verify that every plot types ends up with consistent levels.
Here's my demo notebook:
https://gist.github.com/shoyer/e6fafbc672021600d9f3
and a teaser:
The main difference in functionality is in my PR is that `vmin` and `vmax` _cannot_ be set independently of `levels`, if levels is provided as a list. That seemed a little too flexible, and this way we can get a consistent result across all four plot types. Are there any cases where you _would_ want to set `vmin`/`vmax` to something other than the first and last levels?
Also, I entirely replaced the levels calculation in contour/contourf with our calculated levels instead of merely trying to replicate it. That ensures things are guaranteed to be exactly identical across all plot types.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-127471969,https://api.github.com/repos/pydata/xarray/issues/509,127471969,MDEyOklzc3VlQ29tbWVudDEyNzQ3MTk2OQ==,2443309,2015-08-04T04:10:44Z,2015-08-04T04:10:44Z,MEMBER,"@shoyer - This last commit (119c1c8) should have addressed the issues you brought up. I updated my examples a bit to show how things are working:
``` python
%matplotlib inline
import matplotlib.pyplot as plt
import numpy as np
import xray
# sample DataArray
x = np.arange(start=0, stop=10, step=2)
y = np.arange(start=9, stop=-7, step=-3)
xy = np.dstack(np.meshgrid(x, y))
distance = np.linalg.norm(xy, axis=2)
distance = xray.DataArray(distance, list(zip(('y', 'x'), (y, x))))
# Sample plots
fig, axes = plt.subplots(3, 2, figsize=(8, 8), sharex=True, sharey=True)
distance.plot(ax=axes[0, 0])
axes[0, 0].set_title('Default')
distance.plot(vmin=0, vmax=12, levels=6, ax=axes[1, 0])
axes[1, 0].set_title('Setting with integer levels')
distance.plot(levels=[1, 2, 4, 5, 7, 9], extend='max', cmap='Spectral', ax=axes[0, 1])
axes[0, 1].set_title('Setting with list of levels')
flatui = [""#9b59b6"", ""#3498db"", ""#95a5a6"", ""#e74c3c"", ""#34495e"", ""#2ecc71""]
distance.plot(levels=[1, 2, 4, 5, 7], cmap=flatui, extend='both', ax=axes[1, 1])
axes[1, 1].set_title('Using custom list of colors')
distance.plot.contourf(ax=axes[2, 0])
axes[2, 0].set_title('Default contourf')
distance.plot.contourf(levels=4, ax=axes[2, 1])
axes[2, 1].set_title('contourf w/ int levels')
plt.tight_layout()
```
If the user sets the `extend`, `vmax`, or `vmin` arguments, those are not overridden. This is shown in the top right plot where I set `extend='max'` even though the min of the data is less than the min of `levels`. This results in the data less than the min of `levels` not being show. For the same reason, we also don't use the `MaxNLocator` if `vmin` or `vmax` was provided.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-127364421,https://api.github.com/repos/pydata/xarray/issues/509,127364421,MDEyOklzc3VlQ29tbWVudDEyNzM2NDQyMQ==,1217238,2015-08-03T18:35:04Z,2015-08-03T18:35:04Z,MEMBER,"> Options for when levels is provided and extend == None:
I would opt for your solution 2. I think this basically means using `levels[0]` and `levels[-1]` if levels are provided explicitly instead of `vmin`/`vmax` (which are being ignored anyways).
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-127357707,https://api.github.com/repos/pydata/xarray/issues/509,127357707,MDEyOklzc3VlQ29tbWVudDEyNzM1NzcwNw==,2443309,2015-08-03T18:14:10Z,2015-08-03T18:14:10Z,MEMBER,"> The logic for inferring the extend keyword argument needs to be updated to handle levels:
How do you want to handle this? Options for when `levels` is provided and `extend == None`:
1. Don't extend. This will result in data outside the range of `levels` being masked out,
2. Extend if the min/max of the data exceed the range of `levels`, or
3. Require extend to be specified when `levels` is provided.
I will add the `MaxNLocator` ticker for integer `levels`. I agree this is the way to go.
I think this logic will also help address your 4th point:
> ...contourf currently crashes if you supply levels as an integer. This should be fixed, probably by converting levels into a 1d array / list if they are supplied as an integer before passing it into contourf. This would actually be more broadly useful, because currently there is no way to supply a non-default integer number of levels with contourf -- matplotlb appears to only expose the N argument when it is used positionally.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-127164584,https://api.github.com/repos/pydata/xarray/issues/509,127164584,MDEyOklzc3VlQ29tbWVudDEyNzE2NDU4NA==,1217238,2015-08-03T08:39:18Z,2015-08-03T08:39:18Z,MEMBER,"Looking at the matplotlib source code, here's how they figure out levels in contour/contourf:
https://github.com/matplotlib/matplotlib/blob/714d18788320325d0bff75184f62d472f67ceb91/lib/matplotlib/contour.py#L1143
It looks like they use `MaxNLocator` to do this:
http://matplotlib.org/api/ticker_api.html#matplotlib.ticker.MaxNLocator
It should be pretty straightforward to use that here.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-127163088,https://api.github.com/repos/pydata/xarray/issues/509,127163088,MDEyOklzc3VlQ29tbWVudDEyNzE2MzA4OA==,1217238,2015-08-03T08:29:34Z,2015-08-03T08:32:11Z,MEMBER,"Some feedback:
1. matplotlib seems to have nice heuristics for picking level splits with contour plots. I wonder if it would be feasible to copy that logic here when setting our own discrete levels? Compare:
`ds.t2m[3].plot(levels=6)`
vs `ds.t2m[3].plot.contourf()`
2. The logic for inferring the `extend` keyword argument needs to be updated to handle `levels`:
`ds.t2m[3].plot(robust=True, levels=[200, 250, 260, 270, 280, 290, 350])`
3.`imshow`, `pcolormesh` and `contourf` seem to deal with an explicit list of `levels` the exact same way. That's a relief. The plots look exactly the same.
4. As you noted, `contourf` currently crashes if you supply `levels` as an integer. This should be fixed, probably by converting `levels` into a 1d array / list if they are supplied as an integer before passing it into `contourf`. This would actually be more broadly useful, because currently there is no way to supply a non-default integer number of levels with `contourf` -- matplotlb appears to only expose the `N` argument when it is used positionally.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509
https://github.com/pydata/xarray/pull/509#issuecomment-127076768,https://api.github.com/repos/pydata/xarray/issues/509,127076768,MDEyOklzc3VlQ29tbWVudDEyNzA3Njc2OA==,2443309,2015-08-02T22:16:17Z,2015-08-02T22:16:17Z,MEMBER,"These last two commits have resolved the two issues I brought up above.
","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,98629509