Add Support for Series Histograms (#95)

* add support for series plotting
* update docs for series plotting support
* add tests for series plotting
* fix typo
* adds comment to ed_hist_series

docs/source/reference/api/eland.Series.hist.rst

@@ -0,0 +1,8 @@
+eland.Series.hist
+====================
+
+.. currentmodule:: eland
+
+.. automethod:: Series.hist
+.. image:: eland-Series-hist-1.png
+

eland/operations.py

@@ -14,6 +14,7 @@
 
 import copy
 from collections import OrderedDict
+import warnings
 
 import pandas as pd
 
@@ -258,12 +259,10 @@ class Operations:
 
         for field in numeric_source_fields:
             body.hist_aggs(field, field, min_aggs, max_aggs, num_bins)
-
         response = query_compiler._client.search(
             index=query_compiler._index_pattern,
             size=0,
             body=body.to_search_body())
-
         # results are like
         # "aggregations" : {
         #     "DistanceKilometers" : {
@@ -293,6 +292,19 @@ class Operations:
         # weights = [10066.,   263.,   386.,   264.,   273.,   390.,   324.,   438.,   261.,   252.,    142.]
         # So sum last 2 buckets
         for field in numeric_source_fields:
+
+            # in case of series let plotting.ed_hist_series thrown an exception
+            if not response.get('aggregations'):
+                continue
+
+            # in case of dataframe, throw warning that field is excluded
+            if not response['aggregations'].get(field):
+                warnings.warn("{} has no meaningful histogram interval and will be excluded. "
+                                "All values 0."
+                            .format(field),
+                            UserWarning)
+                continue
+
             buckets = response['aggregations'][field]['buckets']
 
             bins[field] = []

eland/plotting.py

@@ -86,3 +86,48 @@ def ed_hist_frame(ed_df, column=None, by=None, grid=True, xlabelsize=None,
     fig.subplots_adjust(wspace=0.3, hspace=0.3)
 
     return axes
+
+def ed_hist_series(ed_s, column=None, by=None, grid=True, xlabelsize=None,
+                  xrot=None, ylabelsize=None, yrot=None, ax=None,
+                  figsize=None, layout=None, bins=10, **kwds):
+    """
+    See :pandas_api_docs:`pandas.Series.hist` for usage.
+
+    Notes
+    -----
+    Derived from ``pandas.plotting._core.hist_frame 0.24.2`` - TODO update to ``0.25.1``
+
+
+    Examples
+    --------
+    >>> df = ed.DataFrame('localhost', 'ecommerce')
+    >>> hist = df['taxful_total_price'].hist(figsize=[10,10]) # doctest: +SKIP
+    """
+    # this is mostly the same code as above, it has been split out
+    # to a series specific method now so we can expand series plotting
+
+
+    # Start with empty pandas data frame derived from
+    ed_s_bins, ed_s_weights = ed_s._hist(num_bins=bins)
+
+    if by is not None:
+        raise NotImplementedError("TODO")
+
+    # raise error rather than warning when series is not plottable
+    if ed_s_bins.empty:
+        raise ValueError("{} has no meaningful histogram interval. All values 0."
+                        .format(ed_s.name))
+
+    naxes = len(ed_s_bins.columns)
+    fig, axes = _subplots(naxes=naxes, ax=ax, squeeze=False, figsize=figsize, layout=layout)
+    _axes = _flatten(axes)
+    for i, col in enumerate(com.try_sort(ed_s_bins.columns)):
+        ax = _axes[i]
+        ax.hist(ed_s_bins[col][:-1], bins=ed_s_bins[col], weights=ed_s_weights[col], **kwds)
+        ax.grid(grid)
+
+    _set_ticks_props(axes, xlabelsize=xlabelsize, xrot=xrot,
+                     ylabelsize=ylabelsize, yrot=yrot)
+    fig.subplots_adjust(wspace=0.3, hspace=0.3)
+
+    return axes

eland/query.py

@@ -148,8 +148,11 @@ class Query:
                 "interval": interval
             }
         }
+
+        if not min == max == 0:
             self._aggs[name] = agg
 
+
     def to_search_body(self):
         if self._query.empty():
             if self._aggs:

eland/series.py

@@ -40,6 +40,7 @@ from pandas.io.common import _expand_user, _stringify_path
 from eland import NDFrame
 from eland.common import DEFAULT_NUM_ROWS_DISPLAYED, docstring_parameter
 from eland.filter import NotFilter, Equal, Greater, Less, GreaterEqual, LessEqual, ScriptFilter, IsIn
+import eland.plotting as gfx
 
 
 def _get_method_name():
@@ -106,6 +107,8 @@ class Series(NDFrame):
             index_field=index_field,
             query_compiler=query_compiler)
 
+    hist = gfx.ed_hist_series
+
     @property
     def empty(self):
         """Determines if the Series is empty.

eland/tests/plotting/test_series_hist_pytest.py

@@ -0,0 +1,33 @@
+#  Copyright 2019 Elasticsearch BV
+#
+#      Licensed under the Apache License, Version 2.0 (the "License");
+#      you may not use this file except in compliance with the License.
+#      You may obtain a copy of the License at
+#
+#          http://www.apache.org/licenses/LICENSE-2.0
+#
+#      Unless required by applicable law or agreed to in writing, software
+#      distributed under the License is distributed on an "AS IS" BASIS,
+#      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#      See the License for the specific language governing permissions and
+#      limitations under the License.
+
+# File called _pytest for PyCharm compatability
+import pytest
+from matplotlib.testing.decorators import check_figures_equal
+
+from eland.tests.common import TestData
+
+
+@check_figures_equal(extensions=['png'])
+def test_plot_hist(fig_test, fig_ref):
+    test_data = TestData()
+
+    pd_flights = test_data.pd_flights()['FlightDelayMin']
+    ed_flights = test_data.ed_flights()['FlightDelayMin']
+
+    pd_ax = fig_ref.subplots()
+    ed_ax = fig_test.subplots()
+
+    pd_flights.hist(ax=pd_ax)
+    ed_flights.hist(ax=ed_ax)

eland/tests/series/test_hist_pytest.py

@@ -0,0 +1,49 @@
+#  Copyright 2019 Elasticsearch BV
+#
+#      Licensed under the Apache License, Version 2.0 (the "License");
+#      you may not use this file except in compliance with the License.
+#      You may obtain a copy of the License at
+#
+#          http://www.apache.org/licenses/LICENSE-2.0
+#
+#      Unless required by applicable law or agreed to in writing, software
+#      distributed under the License is distributed on an "AS IS" BASIS,
+#      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#      See the License for the specific language governing permissions and
+#      limitations under the License.
+
+# File called _pytest for PyCharm compatability
+
+import numpy as np
+import pandas as pd
+from pandas.util.testing import assert_almost_equal
+import pytest
+
+from eland.tests.common import TestData
+
+
+class TestSeriesFrameHist(TestData):
+
+    def test_flight_delay_min_hist(self):
+        pd_flights = self.pd_flights()
+        ed_flights = self.ed_flights()
+
+        num_bins = 10
+
+        # pandas data
+        pd_flightdelaymin = np.histogram(pd_flights['FlightDelayMin'], num_bins)
+
+        pd_bins = pd.DataFrame(
+            {'FlightDelayMin': pd_flightdelaymin[1]})
+        pd_weights = pd.DataFrame(
+            {'FlightDelayMin': pd_flightdelaymin[0]})
+
+        ed_bins, ed_weights = ed_flights['FlightDelayMin']._hist(num_bins=num_bins)
+
+        # Numbers are slightly different
+        assert_almost_equal(pd_bins, ed_bins)
+        assert_almost_equal(pd_weights, ed_weights)
+
+    def test_invalid_hist(self):
+        with pytest.raises(ValueError):
+            assert self.ed_ecommerce()['products.tax_amount'].hist()