added DatFrame reports filters head and tail, closes #1633

docs/reports.rst

@@ -137,7 +137,7 @@ Available filters for DataFrames:
 
   If your DataFrame has 12 rows and you use ``maxrows(10, Other)`` as filter, you'll get a table that shows the first 9 rows as-is and sums up the remaining 3 rows under the label ``Other``. If your data is unsorted, combine it with the ``sortasc``/``sortdesc`` to make sure the correct rows are aggregated.
 
-  See also: ``aggsmall``
+  See also: ``aggsmall``, ``head``, ``tail``
 
   Syntax::
 
@@ -155,7 +155,7 @@ Available filters for DataFrames:
 
   If the values in the specified row are below the threshold values, they will be summed up in a single row.
 
-  See also: ``maxrows``
+  See also: ``maxrows``, ``head``, ``tail``
 
   Syntax::
 
@@ -169,6 +169,22 @@ Available filters for DataFrames:
   {{ df | aggsmall(0.5, 1, Other, 0) }}
   {{ df | sortasc(1)| noindex | aggsmall(0.1, 2, Other) }}
 
+* **head**: Only show the top n rows
+
+  See also: ``maxrows``, ``aggsmall``, ``tail``
+
+  Example::
+
+  {{ df | head(3) }}
+
+* **tail**: Only show the bottom n rows
+
+  See also: ``maxrows``, ``aggsmall``, ``head``
+
+  Example::
+
+  {{ df | tail(5) }}
+
 .. _excel_tables_reports:
 
 Excel Tables

docs/whatsnew.rst

@@ -1,6 +1,11 @@
 What's New
 ==========
 
+v0.24.1 (Jun 27, 2021)
+----------------------
+
+* :guilabel:`PRO` [Enhancement]: The reports package now offers the additional DataFrame filters ``head`` and ``tail``, see :ref:`xlwings Reports<reports_quickstart>` (:issue:`1633`).
+
 v0.24.0 (Jun 25, 2021)
 ----------------------
 
@@ -10,7 +15,7 @@ v0.24.0 (Jun 25, 2021)
 * [Enhancement] Removed dependency on pillow/PIL to properly size images via ``pictures.add()``.
 * [Bug Fix] Various fixes with scaling and positioning images via ``pictures.add()`` (:issue:`1491`).
 * [Feature] New methods :meth:`mypicture.lock_aspect_ratio <xlwings.Picture.lock_aspect_ratio>` and :meth:`myapp.cut_copy_mode <xlwings.App.cut_copy_mode>` (:issue:`1622` and :issue:`1625`).
-* :guilabel:`PRO`: Reports: DataFrames and Images are now offering various filters to influence the behavior of how DataFrames and Images are displayed, giving the template designer the ability to change a lot of things that previously had to be taken care of by the Python developer. For example, to hide a DataFrame's index, you can now do ``{{ df | noindex }}`` or to scale the image to double its size, you can do ``{{ img | scale(2) }}``. You'll find all available filters under :ref:`xlwings Reports<reports_quickstart>` (:issue:`1602`).
+* :guilabel:`PRO` [Feature]: Reports: DataFrames and Images are now offering various filters to influence the behavior of how DataFrames and Images are displayed, giving the template designer the ability to change a lot of things that previously had to be taken care of by the Python developer. For example, to hide a DataFrame's index, you can now do ``{{ df | noindex }}`` or to scale the image to double its size, you can do ``{{ img | scale(2) }}``. You'll find all available filters under :ref:`xlwings Reports<reports_quickstart>` (:issue:`1602`).
 
 
 **Breaking changes**:

tests/reports/test_report.py

@@ -224,7 +224,7 @@ def tearDown(self):
 
     def test_df_filters(self):
         wb = create_report('template1.xlsx', 'output.xlsx', **data)
-        self.assertEqual(wb.sheets['df_filters']['A1:E76'].value, wb.sheets['df_filters']['G1:K76'].value)
+        self.assertEqual(wb.sheets['df_filters']['A1:E114'].value, wb.sheets['df_filters']['G1:K114'].value)
 
     def test_df_filters_in_frames(self):
         wb = create_report('df_filter_frame.xlsx', 'output.xlsx', **data)

xlwings/pro/reports/main.py

@@ -172,6 +172,10 @@ def render_template(sheet, **data):
                                         if len(filter_args['aggsmall']) > 3:
                                             result.iloc[-1, filter_args['aggsmall'][3].as_const()] = other_name
                                     result = result.drop(columns=dummy_col)
+                                if 'head' in filter_names:
+                                    result = result.head(filter_args['head'][0].as_const())
+                                if 'tail' in filter_names:
+                                    result = result.tail(filter_args['tail'][0].as_const())
                                 if 'columns' in filter_names:
                                     # Must come after maxrows/aggsmall as the duplicate column names would cause issues
                                     columns = [arg.as_const() for arg in filter_args['columns']]