Adding example for coords argument in documentation (arviz-devs#1566)

* Added Dataframe to InfData Example

* Added coords argument examples in documentation

* Updated coords argument example in docstring

CHANGELOG.md

@@ -2,7 +2,7 @@
 
 ## v0.x.x Unreleased
 ### New features
-* Added `to_zarr` and `from_zarr` methods to InferenceData ([1518](https://github.com/arviz-devs/arviz/pull/1535))
+* Added `to_zarr` and `from_zarr` methods to InferenceData ([1518](https://github.com/arviz-devs/arviz/pull/1518))
 * Added confidence interval band to auto-correlation plot ([1535](https://github.com/arviz-devs/arviz/pull/1535))
 
 ### Maintenance and fixes
@@ -17,6 +17,7 @@
 
 ### Documentation
 * Added an example for converting dataframe to InferenceData ([1556](https://github.com/arviz-devs/arviz/pull/1556))
+* Added example for `coords` argument in `plot_posterior` docstring ([1566](https://github.com/arviz-devs/arviz/pull/1566))
 
 ## v0.11.1 (2021 Feb 2)
 ### Maintenance and fixes

arviz/plots/posteriorplot.py

@@ -149,6 +149,13 @@ def plot_posterior(
         >>> rope = {'mu': [{'rope': (-2, 2)}], 'theta': [{'school': 'Choate', 'rope': (2, 4)}]}
         >>> az.plot_posterior(data, var_names=['mu', 'theta'], rope=rope)
 
+    Using `coords` argument to plot only a subset of data
+
+    .. plot::
+        :context: close-figs
+
+        >>> coords = {"school": ["Choate","Phillips Exeter"]}
+        >>> az.plot_posterior(data, var_names=["mu", "theta"], coords=coords)
 
     Add reference lines
 

doc/source/getting_started/CreatingInferenceData.ipynb

@@ -29507,4 +29507,4 @@
  },
  "nbformat": 4,
  "nbformat_minor": 4
-}
+}