From aa89e8a6e7788438c6e83064dcdf7ac5b1250c82 Mon Sep 17 00:00:00 2001
From: ilia_timofeev <ilia.timofeev@gmail.com>
Date: Tue, 21 May 2019 02:10:29 +0300
Subject: [PATCH 1/2] violine plot

---
 altair/examples/violine_plot.py | 50 +++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 altair/examples/violine_plot.py

diff --git a/altair/examples/violine_plot.py b/altair/examples/violine_plot.py
new file mode 100644
index 000000000..295b792f4
--- /dev/null
+++ b/altair/examples/violine_plot.py
@@ -0,0 +1,50 @@
+"""
+Violinplot
+----------
+This example shows how to make a king of a Violinplot.
+"""
+# category: other charts
+import altair as alt
+from vega_datasets import data
+
+source = data.cars.url
+
+violinplot =  alt.Chart(source).transform_filter(
+    alt.FieldGTPredicate(field='Miles_per_Gallon',gt=0)
+).transform_bin(
+    ['bin_max', 'bin_min'], field='Miles_per_Gallon', bin=alt.Bin(maxbins=20)
+).transform_calculate(
+    binned='(datum["bin_max"]+datum["bin_min"])/2'
+).transform_aggregate(
+    value_count='count()', groupby=['Origin', 'binned']
+).transform_impute(
+    impute='value_count', groupby=['Origin'], key='binned', value=0
+).mark_area(
+    interpolate='monotone',
+    orient='horizontal'
+).encode(
+    x=alt.X(
+        'value_count:Q',
+        title=None,
+        stack='center',
+        axis=alt.Axis(labels=False, values=[0],grid=False, ticks=True),
+    ),
+    y=alt.Y('binned:Q', bin='binned', title='Miles per Gallon'),
+    color=alt.Color('Origin:N', legend=None),
+    column=alt.Column(
+        'Origin:N',
+        header=alt.Header(
+            titleOrient='bottom',
+            labelOrient='bottom',
+            labelPadding=0,
+        ),
+    ),
+).properties( 
+    width=80 
+).configure_facet(
+    spacing=0
+).configure_view(
+    stroke=None
+)
+
+violinplot
\ No newline at end of file

From d7b0e7f11e68480899307656a5963705eb8815fc Mon Sep 17 00:00:00 2001
From: ilia_timofeev <ilia.timofeev@gmail.com>
Date: Thu, 23 May 2019 23:24:05 +0300
Subject: [PATCH 2/2] datum notation

---
 altair/examples/violine_plot.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/altair/examples/violine_plot.py b/altair/examples/violine_plot.py
index 295b792f4..3d78cdc9b 100644
--- a/altair/examples/violine_plot.py
+++ b/altair/examples/violine_plot.py
@@ -5,16 +5,17 @@
 """
 # category: other charts
 import altair as alt
+from altair import datum
 from vega_datasets import data
 
 source = data.cars.url
 
 violinplot =  alt.Chart(source).transform_filter(
-    alt.FieldGTPredicate(field='Miles_per_Gallon',gt=0)
+    datum.Miles_per_Gallon > 0
 ).transform_bin(
     ['bin_max', 'bin_min'], field='Miles_per_Gallon', bin=alt.Bin(maxbins=20)
 ).transform_calculate(
-    binned='(datum["bin_max"]+datum["bin_min"])/2'
+    binned=(datum.bin_max + datum.bin_min) / 2
 ).transform_aggregate(
     value_count='count()', groupby=['Origin', 'binned']
 ).transform_impute(