CDash: Add comparison tables

Signed-off-by: Tibor Frank <tifrank@cisco.com>
Change-Id: I8ce9e670721e1fdb1f297b3bfb8f0d8ffb916713

10 files changed, 1380 insertions, 1 deletions

diff --git a/csit.infra.dash/app/cdash/__init__.py b/csit.infra.dash/app/cdash/__init__.py
index 77722c78bd..0bc8bf7a19 100644
--- a/csit.infra.dash/app/cdash/__init__.py
+++ b/csit.infra.dash/app/cdash/__init__.py
@@ -93,6 +93,12 @@ def init_app():
             data_iterative=data["iterative"]
         )
 
+        from .comparisons.comparisons import init_comparisons
+        app = init_comparisons(
+            app,
+            data_iterative=data["iterative"]
+        )
+
     return app
 
 
diff --git a/csit.infra.dash/app/cdash/comparisons/__init__.py b/csit.infra.dash/app/cdash/comparisons/__init__.py
new file mode 100644
index 0000000000..f0d52c25b6
--- /dev/null
+++ b/csit.infra.dash/app/cdash/comparisons/__init__.py
@@ -0,0 +1,12 @@
+# Copyright (c) 2023 Cisco and/or its affiliates.
+# 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.
diff --git a/csit.infra.dash/app/cdash/comparisons/comparisons.py b/csit.infra.dash/app/cdash/comparisons/comparisons.py
new file mode 100644
index 0000000000..bc42085dc8
--- /dev/null
+++ b/csit.infra.dash/app/cdash/comparisons/comparisons.py
@@ -0,0 +1,51 @@
+# Copyright (c) 2023 Cisco and/or its affiliates.
+# 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.
+
+"""Instantiate the Report Dash application.
+"""
+
+import dash
+import pandas as pd
+
+from ..utils.constants import Constants as C
+from .layout import Layout
+
+
+def init_comparisons(
+        server,
+        data_iterative: pd.DataFrame
+    ) -> dash.Dash:
+    """Create a Plotly Dash dashboard.
+
+    :param server: Flask server.
+    :type server: Flask
+    :returns: Dash app server.
+    :rtype: Dash
+    """
+
+    dash_app = dash.Dash(
+        server=server,
+        routes_pathname_prefix=C.COMP_ROUTES_PATHNAME_PREFIX,
+        external_stylesheets=C.EXTERNAL_STYLESHEETS,
+        title=C.COMP_TITLE
+    )
+
+    layout = Layout(
+        app=dash_app,
+        data_iterative=data_iterative,
+        html_layout_file=C.HTML_LAYOUT_FILE
+    )
+    dash_app.index_string = layout.html_layout
+    dash_app.layout = layout.add_content()
+
+    return dash_app.server
diff --git a/csit.infra.dash/app/cdash/comparisons/layout.py b/csit.infra.dash/app/cdash/comparisons/layout.py
new file mode 100644
index 0000000000..bb4c6dd93c
--- /dev/null
+++ b/csit.infra.dash/app/cdash/comparisons/layout.py
@@ -0,0 +1,982 @@
+# Copyright (c) 2023 Cisco and/or its affiliates.
+# 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.
+
+"""Plotly Dash HTML layout override.
+"""
+
+import pandas as pd
+import dash_bootstrap_components as dbc
+
+from flask import Flask
+from dash import dcc, html, dash_table, callback_context, no_update, ALL
+from dash import Input, Output, State
+from dash.exceptions import PreventUpdate
+from dash.dash_table.Format import Format, Scheme
+from ast import literal_eval
+
+from ..utils.constants import Constants as C
+from ..utils.control_panel import ControlPanel
+from ..utils.trigger import Trigger
+from ..utils.url_processing import url_decode
+from ..utils.utils import generate_options, gen_new_url
+from .tables import comparison_table
+
+
+# Control panel partameters and their default values.
+CP_PARAMS = {
+    "dut-val": str(),
+    "dutver-opt": list(),
+    "dutver-dis": True,
+    "dutver-val": str(),
+    "infra-opt": list(),
+    "infra-dis": True,
+    "infra-val": str(),
+    "core-opt": list(),
+    "core-val": list(),
+    "frmsize-opt": list(),
+    "frmsize-val": list(),
+    "ttype-opt": list(),
+    "ttype-val": list(),
+    "cmp-par-opt": list(),
+    "cmp-par-dis": True,
+    "cmp-par-val": str(),
+    "cmp-val-opt": list(),
+    "cmp-val-dis": True,
+    "cmp-val-val": str(),
+    "normalize-val": list()
+}
+
+# List of comparable parameters.
+CMP_PARAMS = {
+    "dutver": "Release and Version",
+    "infra": "Infrastructure",
+    "frmsize": "Frame Size",
+    "core": "Number of Cores",
+    "ttype": "Test Type"
+}
+
+
+class Layout:
+    """The layout of the dash app and the callbacks.
+    """
+
+    def __init__(
+            self,
+            app: Flask,
+            data_iterative: pd.DataFrame,
+            html_layout_file: str
+        ) -> None:
+        """Initialization:
+        - save the input parameters,
+        - prepare data for the control panel,
+        - read HTML layout file,
+
+        :param app: Flask application running the dash application.
+        :param data_iterative: Iterative data to be used in comparison tables.
+        :param html_layout_file: Path and name of the file specifying the HTML
+            layout of the dash application.
+        :type app: Flask
+        :type data_iterative: pandas.DataFrame
+        :type html_layout_file: str
+        """
+
+        # Inputs
+        self._app = app
+        self._html_layout_file = html_layout_file
+        self._data = data_iterative
+
+        # Get structure of tests:
+        tbs = dict()
+        cols = [
+            "job", "test_id", "test_type", "dut_type", "dut_version", "tg_type",
+            "release", "passed"
+        ]
+        for _, row in self._data[cols].drop_duplicates().iterrows():
+            lst_job = row["job"].split("-")
+            dut = lst_job[1]
+            dver = f"{row['release']}-{row['dut_version']}"
+            tbed = "-".join(lst_job[-2:])
+            lst_test_id = row["test_id"].split(".")
+
+            suite = lst_test_id[-2].replace("2n1l-", "").replace("1n1l-", "").\
+                replace("2n-", "")
+            test = lst_test_id[-1]
+            nic = suite.split("-")[0]
+            for driver in C.DRIVERS:
+                if driver in test:
+                    drv = driver.replace("-", "_")
+                    test = test.replace(f"{driver}-", "")
+                    break
+            else:
+                drv = "dpdk"
+            infra = "-".join((tbed, nic, drv))
+            lst_test = test.split("-")
+            fsize = lst_test[0]
+            core = lst_test[1] if lst_test[1] else "8C"
+
+            if tbs.get(dut, None) is None:
+                tbs[dut] = dict()
+            if tbs[dut].get(dver, None) is None:
+                tbs[dut][dver] = dict()
+            if tbs[dut][dver].get(infra, None) is None:
+                tbs[dut][dver][infra] = dict()
+                tbs[dut][dver][infra]["core"] = list()
+                tbs[dut][dver][infra]["fsize"] = list()
+                tbs[dut][dver][infra]["ttype"] = list()
+            if core.upper() not in tbs[dut][dver][infra]["core"]:
+                tbs[dut][dver][infra]["core"].append(core.upper())
+            if fsize.upper() not in tbs[dut][dver][infra]["fsize"]:
+                tbs[dut][dver][infra]["fsize"].append(fsize.upper())
+            if row["test_type"] == "mrr":
+                if "MRR" not in tbs[dut][dver][infra]["ttype"]:
+                    tbs[dut][dver][infra]["ttype"].append("MRR")
+            elif row["test_type"] == "ndrpdr":
+                if "NDR" not in tbs[dut][dver][infra]["ttype"]:
+                    tbs[dut][dver][infra]["ttype"].extend(("NDR", "PDR", ))
+            elif row["test_type"] == "hoststack" and \
+                    row["tg_type"] in ("iperf", "vpp"):
+                if "BPS" not in tbs[dut][dver][infra]["ttype"]:
+                    tbs[dut][dver][infra]["ttype"].append("BPS")
+            elif row["test_type"] == "hoststack" and row["tg_type"] == "ab":
+                if "CPS" not in tbs[dut][dver][infra]["ttype"]:
+                    tbs[dut][dver][infra]["ttype"].extend(("CPS", "RPS", ))
+        self._tbs = tbs
+
+        # Read from files:
+        self._html_layout = str()
+        try:
+            with open(self._html_layout_file, "r") as file_read:
+                self._html_layout = file_read.read()
+        except IOError as err:
+            raise RuntimeError(
+                f"Not possible to open the file {self._html_layout_file}\n{err}"
+            )
+
+        # Callbacks:
+        if self._app is not None and hasattr(self, "callbacks"):
+            self.callbacks(self._app)
+
+    @property
+    def html_layout(self):
+        return self._html_layout
+
+    def add_content(self):
+        """Top level method which generated the web page.
+
+        It generates:
+        - Store for user input data,
+        - Navigation bar,
+        - Main area with control panel and ploting area.
+
+        If no HTML layout is provided, an error message is displayed instead.
+
+        :returns: The HTML div with the whole page.
+        :rtype: html.Div
+        """
+
+        if self.html_layout and self._tbs:
+            return html.Div(
+                id="div-main",
+                className="small",
+                children=[
+                    dbc.Row(
+                        id="row-navbar",
+                        class_name="g-0",
+                        children=[
+                            self._add_navbar()
+                        ]
+                    ),
+                    dbc.Row(
+                        id="row-main",
+                        class_name="g-0",
+                        children=[
+                            dcc.Store(id="store-control-panel"),
+                            dcc.Store(id="store-selected"),
+                            dcc.Location(id="url", refresh=False),
+                            self._add_ctrl_col(),
+                            self._add_plotting_col()
+                        ]
+                    )
+                ]
+            )
+        else:
+            return html.Div(
+                id="div-main-error",
+                children=[
+                    dbc.Alert(
+                        [
+                            "An Error Occured"
+                        ],
+                        color="danger"
+                    )
+                ]
+            )
+
+    def _add_navbar(self):
+        """Add nav element with navigation panel. It is placed on the top.
+
+        :returns: Navigation bar.
+        :rtype: dbc.NavbarSimple
+        """
+        return dbc.NavbarSimple(
+            id="navbarsimple-main",
+            children=[
+                dbc.NavItem(
+                    dbc.NavLink(
+                        C.COMP_TITLE,
+                        disabled=True,
+                        external_link=True,
+                        href="#"
+                    )
+                )
+            ],
+            brand=C.BRAND,
+            brand_href="/",
+            brand_external_link=True,
+            class_name="p-2",
+            fluid=True
+        )
+
+    def _add_ctrl_col(self) -> dbc.Col:
+        """Add column with controls. It is placed on the left side.
+
+        :returns: Column with the control panel.
+        :rtype: dbc.Col
+        """
+        return dbc.Col([
+            html.Div(
+                children=self._add_ctrl_panel(),
+                className="sticky-top"
+            )
+        ])
+
+    def _add_plotting_col(self) -> dbc.Col:
+        """Add column with plots. It is placed on the right side.
+
+        :returns: Column with plots.
+        :rtype: dbc.Col
+        """
+        return dbc.Col(
+            id="col-plotting-area",
+            children=[
+                dbc.Spinner(
+                    children=[
+                        dbc.Row(
+                            id="plotting-area",
+                            class_name="g-0 p-0",
+                            children=[
+                                C.PLACEHOLDER
+                            ]
+                        )
+                    ]
+                )
+            ],
+            width=9
+        )
+
+    def _add_ctrl_panel(self) -> list:
+        """Add control panel.
+
+        :returns: Control panel.
+        :rtype: list
+        """
+
+        reference = [
+            dbc.Row(
+                class_name="g-0 p-1",
+                children=[
+                    dbc.InputGroup(
+                        [
+                            dbc.InputGroupText("DUT"),
+                            dbc.Select(
+                                id={"type": "ctrl-dd", "index": "dut"},
+                                placeholder="Select a Device under Test...",
+                                options=sorted(
+                                    [
+                                        {"label": k, "value": k} \
+                                            for k in self._tbs.keys()
+                                    ],
+                                    key=lambda d: d["label"]
+                                )
+                            )
+                        ],
+                        size="sm"
+                    )
+                ]
+            ),
+            dbc.Row(
+                class_name="g-0 p-1",
+                children=[
+                    dbc.InputGroup(
+                        [
+                            dbc.InputGroupText("CSIT and DUT Version"),
+                            dbc.Select(
+                                id={"type": "ctrl-dd", "index": "dutver"},
+                                placeholder="Select a CSIT and DUT Version...")
+                        ],
+                        size="sm"
+                    )
+                ]
+            ),
+            dbc.Row(
+                class_name="g-0 p-1",
+                children=[
+                    dbc.InputGroup(
+                        [
+                            dbc.InputGroupText("Infra"),
+                            dbc.Select(
+                                id={"type": "ctrl-dd", "index": "infra"},
+                                placeholder=\
+                                    "Select a Physical Test Bed Topology..."
+                            )
+                        ],
+                        size="sm"
+                    )
+                ]
+            ),
+            dbc.Row(
+                class_name="g-0 p-1",
+                children=[
+                    dbc.InputGroup(
+                        [
+                            dbc.InputGroupText("Frame Size"),
+                            dbc.Checklist(
+                                id={"type": "ctrl-cl", "index": "frmsize"},
+                                inline=True,
+                                class_name="ms-2"
+                            )
+                        ],
+                        style={"align-items": "center"},
+                        size="sm"
+                    )
+                ]
+            ),
+            dbc.Row(
+                class_name="g-0 p-1",
+                children=[
+                    dbc.InputGroup(
+                        [
+                            dbc.InputGroupText("Number of Cores"),
+                            dbc.Checklist(
+                                id={"type": "ctrl-cl", "index": "core"},
+                                inline=True,
+                                class_name="ms-2"
+                            )
+                        ],
+                        style={"align-items": "center"},
+                        size="sm"
+                    )
+                ]
+            ),
+            dbc.Row(
+                class_name="g-0 p-1",
+                children=[
+                    dbc.InputGroup(
+                        [
+                            dbc.InputGroupText("Test Type"),
+                            dbc.Checklist(
+                                id={"type": "ctrl-cl", "index": "ttype"},
+                                inline=True,
+                                class_name="ms-2"
+                            )
+                        ],
+                        style={"align-items": "center"},
+                        size="sm"
+                    )
+                ]
+            )
+        ]
+
+        compare = [
+            dbc.Row(
+                class_name="g-0 p-1",
+                children=[
+                    dbc.InputGroup(
+                        [
+                            dbc.InputGroupText("Parameter"),
+                            dbc.Select(
+                                id={"type": "ctrl-dd", "index": "cmpprm"},
+                                placeholder="Select a Parameter..."
+                            )
+                        ],
+                        size="sm"
+                    )
+                ]
+            ),
+            dbc.Row(
+                class_name="g-0 p-1",
+                children=[
+                    dbc.InputGroup(
+                        [
+                            dbc.InputGroupText("Value"),
+                            dbc.Select(
+                                id={"type": "ctrl-dd", "index": "cmpval"},
+                                placeholder="Select a Value..."
+                            )
+                        ],
+                        size="sm"
+                    )
+                ]
+            )
+        ]
+
+        normalize = [
+            dbc.Row(
+                class_name="g-0 p-1",
+                children=[
+                    dbc.InputGroup(
+                        dbc.Checklist(
+                            id="normalize",
+                            options=[{
+                                "value": "normalize",
+                                "label": "Normalize to 2GHz CPU frequency"
+                            }],
+                            value=[],
+                            inline=True,
+                            class_name="ms-2"
+                        ),
+                        style={"align-items": "center"},
+                        size="sm"
+                    )
+                ]
+            )
+        ]
+
+        return [
+            dbc.Row(
+                dbc.Card(
+                    [
+                        dbc.CardHeader(
+                            html.H5("Reference Value")
+                        ),
+                        dbc.CardBody(
+                            children=reference,
+                            class_name="g-0 p-0"
+                        )
+                    ],
+                    color="secondary",
+                    outline=True
+                ),
+                class_name="g-0 p-1"
+            ),
+            dbc.Row(
+                dbc.Card(
+                    [
+                        dbc.CardHeader(
+                            html.H5("Compared Value")
+                        ),
+                        dbc.CardBody(
+                            children=compare,
+                            class_name="g-0 p-0"
+                        )
+                    ],
+                    color="secondary",
+                    outline=True
+                ),
+                class_name="g-0 p-1"
+            ),
+            dbc.Row(
+                dbc.Card(
+                    [
+                        dbc.CardHeader(
+                            html.H5("Normalization")
+                        ),
+                        dbc.CardBody(
+                            children=normalize,
+                            class_name="g-0 p-0"
+                        )
+                    ],
+                    color="secondary",
+                    outline=True
+                ),
+                class_name="g-0 p-1"
+            )
+        ]
+
+    def _get_plotting_area(
+            self,
+            selected: dict,
+            url: str,
+            normalize: bool
+        ) -> list:
+        """Generate the plotting area with all its content.
+
+        :param selected: Selected parameters of tests.
+        :param normalize: If true, the values in tables are normalized.
+        :param url: URL to be displayed in the modal window.
+        :type selected: dict
+        :type normalize: bool
+        :type url: str
+        :returns: List of rows with elements to be displayed in the plotting
+            area.
+        :rtype: list
+        """
+
+        title, df = comparison_table(self._data, selected, normalize)
+
+        if df.empty:
+            return dbc.Row(
+                dbc.Col(
+                    children=dbc.Alert(
+                        "No data for comparison.",
+                        color="danger"
+                    ),
+                    class_name="g-0 p-1",
+                ),
+                class_name="g-0 p-0"
+            )
+
+        cols = list()
+        for idx, col in enumerate(df.columns):
+            if idx == 0:
+                cols.append({
+                    "name": ["", col],
+                    "id": col,
+                    "deletable": False,
+                    "selectable": False,
+                    "type": "text"
+                })
+            else:
+                l_col = col.rsplit(" ", 2)
+                cols.append({
+                    "name": [l_col[0], " ".join(l_col[-2:])],
+                    "id": col,
+                    "deletable": False,
+                    "selectable": False,
+                    "type": "numeric",
+                    "format": Format(precision=2, scheme=Scheme.fixed)
+                })
+
+        return [
+            dbc.Row(
+                children=html.H5(title),
+                class_name="g-0 p-1"
+            ),
+            dbc.Row(
+                children=[
+                    dbc.Col(
+                        children=dash_table.DataTable(
+                            columns=cols,
+                            data=df.to_dict("records"),
+                            merge_duplicate_headers=True,
+                            editable=True,
+                            filter_action="native",
+                            sort_action="native",
+                            sort_mode="multi",
+                            selected_columns=[],
+                            selected_rows=[],
+                            page_action="none",
+                            style_cell={"textAlign": "right"},
+                            style_cell_conditional=[{
+                                "if": {"column_id": "Test Name"},
+                                "textAlign": "left"
+                            }]
+                        ),
+                        class_name="g-0 p-1"
+                    )
+                ],
+                class_name="g-0 p-0"
+            ),
+            dbc.Row(
+                [
+                    dbc.Col([html.Div(
+                        [
+                            dbc.Button(
+                                id="plot-btn-url",
+                                children="Show URL",
+                                class_name="me-1",
+                                color="info",
+                                style={
+                                    "text-transform": "none",
+                                    "padding": "0rem 1rem"
+                                }
+                            ),
+                            dbc.Modal(
+                                [
+                                    dbc.ModalHeader(dbc.ModalTitle("URL")),
+                                    dbc.ModalBody(url)
+                                ],
+                                id="plot-mod-url",
+                                size="xl",
+                                is_open=False,
+                                scrollable=True
+                            ),
+                            dbc.Button(
+                                id="plot-btn-download",
+                                children="Download Data",
+                                class_name="me-1",
+                                color="info",
+                                style={
+                                    "text-transform": "none",
+                                    "padding": "0rem 1rem"
+                                }
+                            ),
+                            dcc.Download(id="download-iterative-data")
+                        ],
+                        className=\
+                            "d-grid gap-0 d-md-flex justify-content-md-end"
+                    )])
+                ],
+                class_name="g-0 p-0"
+            ),
+            dbc.Row(
+                children=C.PLACEHOLDER,
+                class_name="g-0 p-1"
+            )
+        ]
+
+    def callbacks(self, app):
+        """Callbacks for the whole application.
+
+        :param app: The application.
+        :type app: Flask
+        """
+
+        @app.callback(
+            [
+                Output("store-control-panel", "data"),
+                Output("store-selected", "data"),
+                Output("plotting-area", "children"),
+                Output({"type": "ctrl-dd", "index": "dut"}, "value"),
+                Output({"type": "ctrl-dd", "index": "dutver"}, "options"),
+                Output({"type": "ctrl-dd", "index": "dutver"}, "disabled"),
+                Output({"type": "ctrl-dd", "index": "dutver"}, "value"),
+                Output({"type": "ctrl-dd", "index": "infra"}, "options"),
+                Output({"type": "ctrl-dd", "index": "infra"}, "disabled"),
+                Output({"type": "ctrl-dd", "index": "infra"}, "value"),
+                Output({"type": "ctrl-cl", "index": "core"}, "options"),
+                Output({"type": "ctrl-cl", "index": "core"}, "value"),
+                Output({"type": "ctrl-cl", "index": "frmsize"}, "options"),
+                Output({"type": "ctrl-cl", "index": "frmsize"}, "value"),
+                Output({"type": "ctrl-cl", "index": "ttype"}, "options"),
+                Output({"type": "ctrl-cl", "index": "ttype"}, "value"),
+                Output({"type": "ctrl-dd", "index": "cmpprm"}, "options"),
+                Output({"type": "ctrl-dd", "index": "cmpprm"}, "disabled"),
+                Output({"type": "ctrl-dd", "index": "cmpprm"}, "value"),
+                Output({"type": "ctrl-dd", "index": "cmpval"}, "options"),
+                Output({"type": "ctrl-dd", "index": "cmpval"}, "disabled"),
+                Output({"type": "ctrl-dd", "index": "cmpval"}, "value"),
+                Output("normalize", "value")
+            ],
+            [
+                State("store-control-panel", "data"),
+                State("store-selected", "data")
+            ],
+            [
+                Input("url", "href"),
+                Input("normalize", "value"),
+                Input({"type": "ctrl-dd", "index": ALL}, "value"),
+                Input({"type": "ctrl-cl", "index": ALL}, "value"),
+                Input({"type": "ctrl-btn", "index": ALL}, "n_clicks")
+            ]
+        )
+        def _update_application(
+                control_panel: dict,
+                selected: dict,
+                href: str,
+                normalize: list,
+                *_
+            ) -> tuple:
+            """Update the application when the event is detected.
+            """
+
+            ctrl_panel = ControlPanel(CP_PARAMS, control_panel)
+
+            if selected is None:
+                selected = {
+                    "reference": {
+                        "set": False,
+                    },
+                    "compare": {
+                        "set": False,
+                    }
+                }
+
+            # Parse the url:
+            parsed_url = url_decode(href)
+            if parsed_url:
+                url_params = parsed_url["params"]
+            else:
+                url_params = None
+
+            on_draw = False
+            plotting_area = no_update
+
+            trigger = Trigger(callback_context.triggered)
+            if trigger.type == "url" and url_params:
+                process_url = False
+                try:
+                    selected = literal_eval(url_params["selected"][0])
+                    r_sel = selected["reference"]["selection"]
+                    c_sel = selected["compare"]
+                    normalize = literal_eval(url_params["norm"][0])
+                    process_url = bool(
+                        (selected["reference"]["set"] == True) and
+                        (c_sel["set"] == True)
+                    )
+                except (KeyError, IndexError):
+                    pass
+                if process_url:
+                    ctrl_panel.set({
+                        "dut-val": r_sel["dut"],
+                        "dutver-opt": generate_options(
+                            self._tbs[r_sel["dut"]].keys()
+                        ),
+                        "dutver-dis": False,
+                        "dutver-val": r_sel["dutver"],
+                        "infra-opt": generate_options(
+                            self._tbs[r_sel["dut"]][r_sel["dutver"]].keys()
+                        ),
+                        "infra-dis": False,
+                        "infra-val": r_sel["infra"],
+                        "core-opt": generate_options(
+                            self._tbs[r_sel["dut"]][r_sel["dutver"]]\
+                                [r_sel["infra"]]["core"]
+                        ),
+                        "core-val": r_sel["core"],
+                        "frmsize-opt": generate_options(
+                            self._tbs[r_sel["dut"]][r_sel["dutver"]]\
+                                [r_sel["infra"]]["fsize"]
+                        ),
+                        "frmsize-val": r_sel["frmsize"],
+                        "ttype-opt": generate_options(
+                            self._tbs[r_sel["dut"]][r_sel["dutver"]]\
+                                [r_sel["infra"]]["ttype"]
+                        ),
+                        "ttype-val": r_sel["ttype"],
+                        "normalize-val": normalize
+                    })
+                    opts = list()
+                    for itm, label in CMP_PARAMS.items():
+                        if len(ctrl_panel.get(f"{itm}-opt")) > 1:
+                            opts.append({"label": label, "value": itm})
+                    ctrl_panel.set({
+                        "cmp-par-opt": opts,
+                        "cmp-par-dis": False,
+                        "cmp-par-val": c_sel["parameter"]
+                    })
+                    opts = list()
+                    for itm in ctrl_panel.get(f"{c_sel['parameter']}-opt"):
+                        set_val = ctrl_panel.get(f"{c_sel['parameter']}-val")
+                        if isinstance(set_val, list):
+                            if itm["value"] not in set_val:
+                                opts.append(itm)
+                        else:
+                            if itm["value"] != set_val:
+                                opts.append(itm)
+                    ctrl_panel.set({
+                        "cmp-val-opt": opts,
+                        "cmp-val-dis": False,
+                        "cmp-val-val": c_sel["value"]
+                    })
+                    on_draw = True
+            elif trigger.type == "normalize":
+                ctrl_panel.set({"normalize-val": normalize})
+                on_draw = True
+            elif trigger.type == "ctrl-dd":
+                if trigger.idx == "dut":
+                    try:
+                        opts = generate_options(self._tbs[trigger.value].keys())
+                        disabled = False
+                    except KeyError:
+                        opts = list()
+                        disabled = True
+                    ctrl_panel.set({
+                        "dut-val": trigger.value,
+                        "dutver-opt": opts,
+                        "dutver-dis": disabled,
+                        "dutver-val": str(),
+                        "infra-opt": list(),
+                        "infra-dis": True,
+                        "infra-val": str(),
+                        "core-opt": list(),
+                        "core-val": list(),
+                        "frmsize-opt": list(),
+                        "frmsize-val": list(),
+                        "ttype-opt": list(),
+                        "ttype-val": list(),
+                        "cmp-par-opt": list(),
+                        "cmp-par-dis": True,
+                        "cmp-par-val": str(),
+                        "cmp-val-opt": list(),
+                        "cmp-val-dis": True,
+                        "cmp-val-val": str()
+                    })
+                elif trigger.idx == "dutver":
+                    try:
+                        dut = ctrl_panel.get("dut-val")
+                        dver = self._tbs[dut][trigger.value]
+                        opts = generate_options(dver.keys())
+                        disabled = False
+                    except KeyError:
+                        opts = list()
+                        disabled = True
+                    ctrl_panel.set({
+                        "dutver-val": trigger.value,
+                        "infra-opt": opts,
+                        "infra-dis": disabled,
+                        "infra-val": str(),
+                        "core-opt": list(),
+                        "core-val": list(),
+                        "frmsize-opt": list(),
+                        "frmsize-val": list(),
+                        "ttype-opt": list(),
+                        "ttype-val": list(),
+                        "cmp-par-opt": list(),
+                        "cmp-par-dis": True,
+                        "cmp-par-val": str(),
+                        "cmp-val-opt": list(),
+                        "cmp-val-dis": True,
+                        "cmp-val-val": str()
+                    })
+                elif trigger.idx == "infra":
+                    dut = ctrl_panel.get("dut-val")
+                    dver = ctrl_panel.get("dutver-val")
+                    if all((dut, dver, trigger.value, )):
+                        driver = self._tbs[dut][dver][trigger.value]
+                        ctrl_panel.set({
+                            "infra-val": trigger.value,
+                            "core-opt": generate_options(driver["core"]),
+                            "core-val": list(),
+                            "frmsize-opt": generate_options(driver["fsize"]),
+                            "frmsize-val": list(),
+                            "ttype-opt": generate_options(driver["ttype"]),
+                            "ttype-val": list(),
+                            "cmp-par-opt": list(),
+                            "cmp-par-dis": True,
+                            "cmp-par-val": str(),
+                            "cmp-val-opt": list(),
+                            "cmp-val-dis": True,
+                            "cmp-val-val": str()
+                        })
+                elif trigger.idx == "cmpprm":
+                    value = trigger.value
+                    opts = list()
+                    for itm in ctrl_panel.get(f"{value}-opt"):
+                        set_val = ctrl_panel.get(f"{value}-val")
+                        if isinstance(set_val, list):
+                            if itm["value"] not in set_val:
+                                opts.append(itm)
+                        else:
+                            if itm["value"] != set_val:
+                                opts.append(itm)
+                    ctrl_panel.set({
+                        "cmp-par-val": value,
+                        "cmp-val-opt": opts,
+                        "cmp-val-dis": False,
+                        "cmp-val-val": str()
+                    })
+                elif trigger.idx == "cmpval":
+                    ctrl_panel.set({"cmp-val-val": trigger.value})
+                    selected["reference"] = {
+                        "set": True,
+                        "selection": {
+                            "dut": ctrl_panel.get("dut-val"),
+                            "dutver": ctrl_panel.get("dutver-val"),
+                            "infra": ctrl_panel.get("infra-val"),
+                            "core": ctrl_panel.get("core-val"),
+                            "frmsize": ctrl_panel.get("frmsize-val"),
+                            "ttype": ctrl_panel.get("ttype-val")
+                        }
+                    }
+                    selected["compare"] = {
+                        "set": True,
+                        "parameter": ctrl_panel.get("cmp-par-val"),
+                        "value": trigger.value
+                    }
+                    on_draw = True
+            elif trigger.type == "ctrl-cl":
+                ctrl_panel.set({f"{trigger.idx}-val": trigger.value})
+                if all((ctrl_panel.get("core-val"),
+                        ctrl_panel.get("frmsize-val"),
+                        ctrl_panel.get("ttype-val"), )):
+                    opts = list()
+                    for itm, label in CMP_PARAMS.items():
+                        if len(ctrl_panel.get(f"{itm}-opt")) > 1:
+                            if isinstance(ctrl_panel.get(f"{itm}-val"), list):
+                                if len(ctrl_panel.get(f"{itm}-opt")) == \
+                                        len(ctrl_panel.get(f"{itm}-val")):
+                                    continue
+                            opts.append({"label": label, "value": itm})
+                    ctrl_panel.set({
+                        "cmp-par-opt": opts,
+                        "cmp-par-dis": False,
+                        "cmp-par-val": str(),
+                        "cmp-val-opt": list(),
+                        "cmp-val-dis": True,
+                        "cmp-val-val": str()
+                    })
+                else:
+                    ctrl_panel.set({
+                        "cmp-par-opt": list(),
+                        "cmp-par-dis": True,
+                        "cmp-par-val": str(),
+                        "cmp-val-opt": list(),
+                        "cmp-val-dis": True,
+                        "cmp-val-val": str()
+                    })
+
+            if all((on_draw, selected["reference"]["set"],
+                    selected["compare"]["set"], )):
+                plotting_area = self._get_plotting_area(
+                    selected=selected,
+                    normalize=bool(normalize),
+                    url=gen_new_url(
+                        parsed_url,
+                        params={"selected": selected, "norm": normalize}
+                    )
+                )
+
+            ret_val = [ctrl_panel.panel, selected, plotting_area]
+            ret_val.extend(ctrl_panel.values)
+            return ret_val
+
+        @app.callback(
+            Output("plot-mod-url", "is_open"),
+            Input("plot-btn-url", "n_clicks"),
+            State("plot-mod-url", "is_open")
+        )
+        def toggle_plot_mod_url(n, is_open):
+            """Toggle the modal window with url.
+            """
+            if n:
+                return not is_open
+            return is_open
+
+        @app.callback(
+            Output("download-iterative-data", "data"),
+            State("store-selected", "data"),
+            State("normalize", "value"),
+            Input("plot-btn-download", "n_clicks"),
+            prevent_initial_call=True
+        )
+        def _download_trending_data(selected: dict, normalize: list, _: int):
+            """Download the data.
+
+            :param selected: List of tests selected by user stored in the
+                browser.
+            :param normalize: If set, the data is normalized to 2GHz CPU
+                frequency.
+            :type selected: list
+            :type normalize: list
+            :returns: dict of data frame content (base64 encoded) and meta data
+                used by the Download component.
+            :rtype: dict
+            """
+
+            if not selected:
+                raise PreventUpdate
+
+            _, table = comparison_table(self._data, selected, normalize, "csv")
+
+            return dcc.send_data_frame(table.to_csv, C.COMP_DOWNLOAD_FILE_NAME)
diff --git a/csit.infra.dash/app/cdash/comparisons/tables.py b/csit.infra.dash/app/cdash/comparisons/tables.py
new file mode 100644
index 0000000000..14d5d552af
--- /dev/null
+++ b/csit.infra.dash/app/cdash/comparisons/tables.py
@@ -0,0 +1,283 @@
+# Copyright (c) 2023 Cisco and/or its affiliates.
+# 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.
+
+"""The comparison tables.
+"""
+
+import pandas as pd
+
+from numpy import mean, std
+from copy import deepcopy
+from ..utils.constants import Constants as C
+from ..utils.utils import relative_change_stdev
+
+
+def select_comparison_data(
+        data: pd.DataFrame,
+        selected: dict,
+        normalize: bool=False
+    ) -> pd.DataFrame:
+    """Select data for a comparison table.
+
+    :param data: Data to be filtered for the comparison table.
+    :param selected: A dictionary with parameters and their values selected by
+        the user.
+    :param normalize: If True, the data is normalized to CPU frequency
+        Constants.NORM_FREQUENCY.
+    :type data: pandas.DataFrame
+    :type selected: dict
+    :type normalize: bool
+    :returns: A data frame with selected data.
+    :rtype: pandas.DataFrame
+    """
+
+    def _calculate_statistics(
+            data_in: pd.DataFrame,
+            ttype: str,
+            drv: str,
+            norm_factor: float
+        ) -> pd.DataFrame:
+        """Calculates mean value and standard deviation for provided data.
+
+        :param data_in: Input data for calculations.
+        :param ttype: The test type.
+        :param drv: The driver.
+        :param norm_factor: The data normalization factor.
+        :type data_in: pandas.DataFrame
+        :type ttype: str
+        :type drv: str
+        :type norm_factor: float
+        :returns: A pandas dataframe with: test name, mean value, standard
+            deviation and unit.
+        :rtype: pandas.DataFrame
+        """
+        d_data = {
+            "name": list(),
+            "mean": list(),
+            "stdev": list(),
+            "unit": list()
+        }
+        for itm in data_in["test_id"].unique().tolist():
+            itm_lst = itm.split(".")
+            test = itm_lst[-1].rsplit("-", 1)[0]
+            df = data_in.loc[(data_in["test_id"] == itm)]
+            l_df = df[C.VALUE_ITER[ttype]].to_list()
+            if len(l_df) and isinstance(l_df[0], list):
+                tmp_df = list()
+                for l_itm in l_df:
+                    tmp_df.extend(l_itm)
+                l_df = tmp_df
+            d_data["name"].append(f"{test.replace(f'{drv}-', '')}-{ttype}")
+            d_data["mean"].append(int(mean(l_df) * norm_factor))
+            d_data["stdev"].append(int(std(l_df) * norm_factor))
+            d_data["unit"].append(df[C.UNIT[ttype]].to_list()[0])
+        return pd.DataFrame(d_data)
+
+    lst_df = list()
+    for itm in selected:
+        if itm["ttype"] in ("NDR", "PDR"):
+            test_type = "ndrpdr"
+        else:
+            test_type = itm["ttype"].lower()
+
+        dutver = itm["dutver"].split("-", 1)  # 0 -> release, 1 -> dut version
+        tmp_df = pd.DataFrame(data.loc[(
+            (data["passed"] == True) &
+            (data["dut_type"] == itm["dut"]) &
+            (data["dut_version"] == dutver[1]) &
+            (data["test_type"] == test_type) &
+            (data["release"] == dutver[0])
+        )])
+
+        drv = "" if itm["driver"] == "dpdk" else itm["driver"].replace("_", "-")
+        core = str() if itm["dut"] == "trex" else itm["core"].lower()
+        reg_id = \
+            f"^.*[.|-]{itm['nic']}.*{itm['frmsize'].lower()}-{core}-{drv}.*$"
+        tmp_df = tmp_df[
+            (tmp_df.job.str.endswith(itm["tbed"])) &
+            (tmp_df.test_id.str.contains(reg_id, regex=True))
+        ]
+        if itm["driver"] == "dpdk":
+            for drv in C.DRIVERS:
+                tmp_df.drop(
+                    tmp_df[tmp_df.test_id.str.contains(f"-{drv}-")].index,
+                    inplace=True
+                )
+
+        # Change the data type from ndrpdr to one of ("NDR", "PDR")
+        if test_type == "ndrpdr":
+            tmp_df = tmp_df.assign(test_type=itm["ttype"].lower())
+
+        if not tmp_df.empty:
+            tmp_df = _calculate_statistics(
+                tmp_df,
+                itm["ttype"].lower(),
+                itm["driver"],
+                C.NORM_FREQUENCY / C.FREQUENCY[itm["tbed"]] if normalize else 1
+            )
+
+        lst_df.append(tmp_df)
+
+    if len(lst_df) == 1:
+        df = lst_df[0]
+    elif len(lst_df) > 1:
+        df = pd.concat(
+            lst_df,
+            ignore_index=True,
+            copy=False
+        )
+    else:
+        df = pd.DataFrame()
+
+    return df
+
+
+def comparison_table(
+        data: pd.DataFrame,
+        selected: dict,
+        normalize: bool,
+        format: str="html"
+    ) -> tuple:
+    """Generate a comparison table.
+
+    :param data: Iterative data for the comparison table.
+    :param selected: A dictionary with parameters and their values selected by
+        the user.
+    :param normalize: If True, the data is normalized to CPU frequency
+        Constants.NORM_FREQUENCY.
+    :param format: The output format of the table:
+        - html: To be displayed on html page, the values are shown in millions
+          of the unit.
+        - csv: To be downloaded as a CSV file the values are stored in base
+          units.
+    :type data: pandas.DataFrame
+    :type selected: dict
+    :type normalize: bool
+    :type format: str
+    :returns: A tuple with the tabe title and the comparison table.
+    :rtype: tuple[str, pandas.DataFrame]
+    """
+
+    def _create_selection(sel: dict) -> list:
+        """Transform the complex dictionary with user selection to list
+            of simple items.
+
+        :param sel: A complex dictionary with user selection.
+        :type sel: dict
+        :returns: A list of simple items.
+        :rtype: list
+        """
+        l_infra = sel["infra"].split("-")
+        selection = list()
+        for core in sel["core"]:
+            for fsize in sel["frmsize"]:
+                for ttype in sel["ttype"]:
+                    selection.append({
+                        "dut": sel["dut"],
+                        "dutver": sel["dutver"],
+                        "tbed": f"{l_infra[0]}-{l_infra[1]}",
+                        "nic": l_infra[2],
+                        "driver": l_infra[-1].replace("_", "-"),
+                        "core": core,
+                        "frmsize": fsize,
+                        "ttype": ttype
+                    })
+        return selection
+
+    unit_factor, s_unit_factor = (1e6, "M") if format == "html" else (1, str())
+
+    r_sel = deepcopy(selected["reference"]["selection"])
+    c_params = selected["compare"]
+    r_selection = _create_selection(r_sel)
+
+    # Create Table title and titles of columns with data
+    params = list(r_sel)
+    params.remove(c_params["parameter"])
+    lst_title = list()
+    for param in params:
+        value = r_sel[param]
+        if isinstance(value, list):
+            lst_title.append("|".join(value))
+        else:
+            lst_title.append(value)
+    title = "Comparison for: " + "-".join(lst_title)
+    r_name = r_sel[c_params["parameter"]]
+    if isinstance(r_name, list):
+        r_name = "|".join(r_name)
+    c_name = c_params["value"]
+
+    # Select reference data
+    r_data = select_comparison_data(data, r_selection, normalize)
+
+    # Select compare data
+    c_sel = deepcopy(selected["reference"]["selection"])
+    if c_params["parameter"] in ("core", "frmsize", "ttype"):
+        c_sel[c_params["parameter"]] = [c_params["value"], ]
+    else:
+        c_sel[c_params["parameter"]] = c_params["value"]
+
+    c_selection = _create_selection(c_sel)
+    c_data = select_comparison_data(data, c_selection, normalize)
+
+    if r_data.empty or c_data.empty:
+        return str(), pd.DataFrame()
+
+    l_name, l_r_mean, l_r_std, l_c_mean, l_c_std, l_rc_mean, l_rc_std, unit = \
+        list(), list(), list(), list(), list(), list(), list(), set()
+    for _, row in r_data.iterrows():
+        if c_params["parameter"] in ("core", "frmsize", "ttype"):
+            l_cmp = row["name"].split("-")
+            if c_params["parameter"] == "core":
+                c_row = c_data[
+                    (c_data.name.str.contains(l_cmp[0])) &
+                    (c_data.name.str.contains("-".join(l_cmp[2:])))
+                ]
+            elif c_params["parameter"] == "frmsize":
+                c_row = c_data[c_data.name.str.contains("-".join(l_cmp[1:]))]
+            elif c_params["parameter"] == "ttype":
+                regex = r"^" + f"{'-'.join(l_cmp[:-1])}" + r"-.{3}$"
+                c_row = c_data[c_data.name.str.contains(regex, regex=True)]
+        else:
+            c_row = c_data[c_data["name"] == row["name"]]
+        if not c_row.empty:
+            unit.add(f"{s_unit_factor}{row['unit']}")
+            r_mean = row["mean"]
+            r_std = row["stdev"]
+            c_mean = c_row["mean"].values[0]
+            c_std = c_row["stdev"].values[0]
+            l_name.append(row["name"])
+            l_r_mean.append(r_mean / unit_factor)
+            l_r_std.append(r_std / unit_factor)
+            l_c_mean.append(c_mean / unit_factor)
+            l_c_std.append(c_std / unit_factor)
+            delta, d_stdev = relative_change_stdev(r_mean, c_mean, r_std, c_std)
+            l_rc_mean.append(delta)
+            l_rc_std.append(d_stdev)
+
+    s_unit = "|".join(unit)
+    df_cmp = pd.DataFrame.from_dict({
+        "Test Name": l_name,
+        f"{r_name} Mean [{s_unit}]": l_r_mean,
+        f"{r_name} Stdev [{s_unit}]": l_r_std,
+        f"{c_name} Mean [{s_unit}]": l_c_mean,
+        f"{c_name} Stdev [{s_unit}]": l_c_std,
+        "Relative Change Mean [%]": l_rc_mean,
+        "Relative Change Stdev [%]": l_rc_std
+    })
+    df_cmp.sort_values(
+        by="Relative Change Mean [%]",
+        ascending=False,
+        inplace=True
+    )
+
+    return (title, df_cmp)
diff --git a/csit.infra.dash/app/cdash/report/graphs.py b/csit.infra.dash/app/cdash/report/graphs.py
index 870f16a533..9d10efc4f0 100644
--- a/csit.infra.dash/app/cdash/report/graphs.py
+++ b/csit.infra.dash/app/cdash/report/graphs.py
@@ -80,7 +80,7 @@ def graph_iterative(data: pd.DataFrame, sel:dict, layout: dict,
     :param data: Data frame with iterative data.
     :param sel: Selected tests.
     :param layout: Layout of plot.ly graph.
-    :param normalize: If True, the data is normalized to CPU frquency
+    :param normalize: If True, the data is normalized to CPU frequency
         Constants.NORM_FREQUENCY.
     :param data: pandas.DataFrame
     :param sel: dict
diff --git a/csit.infra.dash/app/cdash/routes.py b/csit.infra.dash/app/cdash/routes.py
index 1906d00ee5..71c13edd6d 100644
--- a/csit.infra.dash/app/cdash/routes.py
+++ b/csit.infra.dash/app/cdash/routes.py
@@ -30,6 +30,7 @@ def home():
         description=C.DESCRIPTION,
         trending_title=C.TREND_TITLE,
         report_title=C.REPORT_TITLE,
+        comp_title=C.COMP_TITLE,
         stats_title=C.STATS_TITLE,
         news_title=C.NEWS_TITLE
     )
diff --git a/csit.infra.dash/app/cdash/templates/base_layout.jinja2 b/csit.infra.dash/app/cdash/templates/base_layout.jinja2
index ff31c72178..b799bda3a1 100644
--- a/csit.infra.dash/app/cdash/templates/base_layout.jinja2
+++ b/csit.infra.dash/app/cdash/templates/base_layout.jinja2
@@ -31,6 +31,11 @@
         </a>
       </p>
       <p>
+        <a href="/comparisons/" class="btn btn-primary fw-bold w-25">
+          {{ comp_title }}
+        </a>
+      </p>
+      <p>
         <a href="/stats/" class="btn btn-primary fw-bold w-25">
           {{ stats_title }}
         </a>
diff --git a/csit.infra.dash/app/cdash/utils/constants.py b/csit.infra.dash/app/cdash/utils/constants.py
index 12d7ee5702..1aedb9b96f 100644
--- a/csit.infra.dash/app/cdash/utils/constants.py
+++ b/csit.infra.dash/app/cdash/utils/constants.py
@@ -142,6 +142,7 @@ class Constants:
 
     NORM_FREQUENCY = 2.0  # [GHz]
     FREQUENCY = {  # [GHz]
+        "1n-aws": 1.000,
         "2n-aws": 1.000,
         "2n-dnv": 2.000,
         "2n-clx": 2.300,
@@ -291,6 +292,18 @@ class Constants:
     REPORT_DOWNLOAD_FILE_NAME = "iterative_data.csv"
 
     ############################################################################
+    # Comparisons.
+
+    # The title.
+    COMP_TITLE = "Per Release Performance Comparisons"
+
+    # The pathname prefix for the application.
+    COMP_ROUTES_PATHNAME_PREFIX = "/comparisons/"
+
+    # Default name of downloaded file with selected data.
+    COMP_DOWNLOAD_FILE_NAME = "comparison_data.csv"
+
+    ############################################################################
     # Statistics.
 
     # The title.
diff --git a/csit.infra.dash/app/cdash/utils/utils.py b/csit.infra.dash/app/cdash/utils/utils.py
index 424456088d..68099987d2 100644
--- a/csit.infra.dash/app/cdash/utils/utils.py
+++ b/csit.infra.dash/app/cdash/utils/utils.py
@@ -17,6 +17,7 @@
 import pandas as pd
 import dash_bootstrap_components as dbc
 
+from math import sqrt
 from numpy import isnan
 from dash import dcc
 from datetime import datetime
@@ -391,3 +392,28 @@ def get_list_group_items(
         )
 
     return children
+
+def relative_change_stdev(mean1, mean2, std1, std2):
+    """Compute relative standard deviation of change of two values.
+
+    The "1" values are the base for comparison.
+    Results are returned as percentage (and percentual points for stdev).
+    Linearized theory is used, so results are wrong for relatively large stdev.
+
+    :param mean1: Mean of the first number.
+    :param mean2: Mean of the second number.
+    :param std1: Standard deviation estimate of the first number.
+    :param std2: Standard deviation estimate of the second number.
+    :type mean1: float
+    :type mean2: float
+    :type std1: float
+    :type std2: float
+    :returns: Relative change and its stdev.
+    :rtype: float
+    """
+    mean1, mean2 = float(mean1), float(mean2)
+    quotient = mean2 / mean1
+    first = std1 / mean1
+    second = std2 / mean2
+    std = quotient * sqrt(first * first + second * second)
+    return (quotient - 1) * 100, std * 100