This chapter describes the different ways in which the results of an analysis as well as the basic network input data can be viewed. These include different map views, graphs, tables, and special reports.
There are several ways in which database values and results of a simulation can be viewed directly on the Network Map:
- For the current settings on the Map Browser (see Section 4.6), the nodes and links of the map will be colored according to the color- coding used in the Map Legends (see Section 7.6). The map's coloring will be updated as a new time period is selected in the Browser.
- When the Flyover Map Labeling program preference is selected (see Section 4.9), moving the mouse over any node or link will display its ID label and the value of the current viewing parameter for that node or link in a hint-style box.
- ID labels and viewing parameter values can be displayed next to all nodes and/or links by selecting the appropriate options on the Notation page of the Map Options dialog form (see Section 7.8).
- Nodes or links meeting a specific criterion can be identified by submitting a Map Query (see below).
- You can animate the display of results on the network map either forward or backward in time by using the Animation buttons on the Map Browser. Animation is only available when a node or link viewing parameter is a computed value (e.g., link flow rate can be animated but diameter cannot).
- The map can be printed, copied to the Windows clipboard, or saved as a DXF file or Windows metafile.
A Map Query identifies nodes or links on the network map that meet a specific criterion (e.g., nodes with pressure less than 20 psi, links with velocity above 2 ft/sec, etc.). See Figure 9.1 for an example. To submit a map query:
Figure 9.1 Results of a Map Query
- Select a time period in which to query the map from the Map Browser.
- Select View >> Query or click on the Map Toolbar.
- Fill in the following information in the Query dialog form that appears:
- Select whether to search for Nodes or Links
- Select a parameter to compare against
- Select Above, Below, or Equals
- Enter a value to compare against
- Click the Submit button. The objects that meet the criterion will be highlighted on the map.
- As a new time period is selected in the Browser, the query results are automatically updated.
- You can submit another query using the dialog box or close it by clicking the button in the upper right corner.
After the Query box is closed the map will revert back to its original display.
Analysis results, as well as some design parameters, can be viewed using several different types of graphs. Graphs can be printed, copied to the Windows clipboard, or saved as a data file or Windows metafile. The following types of graphs can be used to view values for a selected parameter (see Figure 9.2 for examples of each):
Type of Plot Description Applies To Time Series Plot Plots value versus time Specific nodes or links over all time periods Profile Plot Plots value versus distance A list of nodes at a specific time Contour Plot Shows regions of the map All nodes at a specific time where values fall within specific intervals Frequency Plot Plots value versus fraction of All nodes or links at a specific time objects at or below the value System Flow Plots total system production Water demand for all nodes over all time periods and consumption versus time Note: When only a single node or link is graphed in a Time Series Plot the graph will also display any measured data residing in a Calibration File that has been registered with the project (see Section 5.3).To create a graph:
The Graph Selection dialog, as pictured in Figure 9.3, is used to select a type of graph and its contents to display. The choices available in the dialog consist of the following:
Item Description Graph Type Selects a graph type Parameter Selects a parameter to graph Time Period Selects a time period to graph (does not apply to Time Series plots) Object Type Selects either Nodes or Links (only Nodes can be graphed on Profile and Contour plots) Items to Graph Selects items to graph (applies only to Time Series and Profile plots) Figure 9.2 Examples of Different Types of Graphs
Figure 9.3 Graph Selection Dialog
Time Series plots and Profile plots require one or more objects be selected for plotting. To select items into the Graph Selection dialog for plotting:
- Select the object (node or link) either on the Network Map or on the Data Browser. (The Graph Selection dialog will remain visible during this process).
- Click the Add button on the Graph Selection dialog to add the selected item to the list.
In place of Step 2, you can also drag the object’s label from the Data Browser onto the Form’s title bar or onto the Items to Graph list box.
The other buttons on the Graph Selection dialog form are used as follows:
Button Purpose Load (Profile Plot Only) Loads a previously saved list of nodes Save (Profile Plot Only) Saves current list of nodes to file Delete Deletes selected item from list Move Up Moves selected item on list up one position Move Down Moves selected item on list down one position To customize the appearance of a graph:
- Make the graph the active window (click on its title bar).
- Select Report >> Options, or click on the Standard Toolbar, or right-click on the graph.
- For a Time Series, Profile, Frequency or System Flow plot, use the resulting Graph Options dialog (Figure 9.4) to customize the graph's appearance.
- For a Contour plot use the resulting Contour Options dialog to customize the plot.
Note: A Time Series, Profile, or Frequency plot can be zoomed by holding down the Ctrl key while drawing a zoom rectangle with the mouse's left button held down. Drawing the rectangle from left to right zooms in, drawing from right to left zooms out. The plot can also be panned in any direction by holding down the Ctrl key and moving the mouse across the plot with the right button held down.
The Graph Options dialog form (Figure 9.4) is used to customize the appearance of an X-Y graph. To use the dialog box:
- Select from among the five tabbed pages that cover the following categories of options:
- General
- Horizontal Axis
- Vertical Axis
- Legend
- Series
- Check the Default box if you wish to use the current settings as defaults for all new graphs as well.
- Select OK to accept your selections.
The items contained on each page of the Graph Options dialog are as follows:
Option Description Panel Color Color of the panel which surrounds the graph’s plotting area Background Color Color of graph's plotting area View in 3D Check if graph should be drawn in 3D 3D Effect Percent Degree to which 3D effect is drawn Main Title Text of graph's main title Font Changes the font used for the main title Figure 9.4 Graph Options Dialog
Horizontal and Vertical Axis Pages
Option Description Minimum Sets minimum axis value (minimum data value is shown in parentheses). Can be left blank. Maximum Sets maximum axis value (maximum data value is shown in parentheses). Can be left blank. Increment Sets increment between axis labels. Can be left blank. Auto Scale If checked then Minimum, Maximum, and Increment settings are ignored. Gridlines Selects type of gridline to draw. Axis Title Text of axis title Font Click to select a font for the axis title. Legend Page
Option Description Position Selects where to place the legend. Color Selects color to use for legend background. Symbol Width Selects width to use (in pixels) to draw symbol portion of the legend. Framed Places a frame around the legend. Visible Makes the legend visible.
The Series page (see Figure 9.4) of the Graph Options dialog controls how individual data series (or curves) are displayed on a graph. To use this page:
Select a data series to work with from the Series combo box.
Edit the title used to identify this series in the legend.
Click the Font button to change the font used for the legend. (Other legend properties are selected on the Legend page of the dialog.)
Select a property of the data series you would like to modify. The choices are:
- Lines
- Markers
- Patterns
- Labels
(Not all properties are available for some types of graphs.)
The data series properties that can be modified include the following:
Category Option Description Lines Style Selects line style. Color Selects line color. Size Selects line thickness (only for solid line style). Visible Determines if line is visible. Markers Style Selects marker style. Color Selects marker color. Size Selects marker size. Visible Determines if marker is visible. Patterns Style Selects pattern style. Color Selects pattern color. Stacking Not used with EPANET. Labels Style Selects what type of information is displayed in the label. Color Selects the color of the label's background. Transparent Determines if graph shows through label or not. Show Arrows Determines if arrows are displayed on pie charts. Visible Determines if labels are visible or not. The Contour Options dialog form (Figure 9.5) is used to customize the appearance of a contour graph. A description of each option is provided below:
Figure 9.5 Contour Plot Options Dialog
Category Option Description Legend Display Legend Toggles display of legend on/off Modify Legend Changes colors and contour intervals Network Backdrop Foreground Color of network image displayed on plot Background Background color used for line contour plot Link Size Thickness of lines used to display network Style Filled Contours Plot uses colored area-filled contours Line Contours Plot uses colored line contours Contour Lines Thickness Thickness of lines used for contour intervals Lines per Level Number of sub-contours per major contour level Default Saves choices as defaults for next contour plot
EPANET allows you to view selected project data and analysis results in a tabular format:
- A Network Table lists properties and results for all nodes or links at a specific period of time.
- A Time Series Table lists properties and results for a specific node or link in all time periods.
Tables can be printed, copied to the Windows clipboard, or saved to file. An example table is shown in Figure 9.6.
To create a table:
- Select View >> Table or click on the Standard Toolbar.
- Use the Table Options dialog box that appears to select:
- the type of table
- the quantities to display in each column
- any filters to apply to the data
Figure 9.6 Example Network Nodes Table
The Table Options dialog form has three tabbed pages as shown in Figure 9.7. All three pages are available when a table is first created. After the table is created, only the Columns and Filters tabs will appear. The options available on each page are as follows:
Figure 9.7 Table Selection Dialog
The Type page of the Table Options dialog is used to select the type of table to create. The choices are:
- All network nodes at a specific time period
- All network links at a specific time period
- All time periods for a specific node
- All time periods for a specific link
Data fields are available for selecting the time period or node/link to which the table applies.
The Columns page of the Table Options dialog form (Figure 9.8) selects the parameters that are displayed in the table’s columns.
- Click the checkbox next to the name of each parameter you wish to include in the table, or if the item is already selected, click in the box to deselect it. (The keyboard's Up and Down Arrow keys can be used to move between the parameter names, and the spacebar can be used to select/deselect choices).
- To sort a Network-type table with respect to the values of a particular parameter, select the parameter from the list and check off the Sorted By box at the bottom of the form. (The sorted parameter does not have to be selected as one of the columns in the table.) Time Series tables cannot be sorted.
Figure 9.8 Columns Page of the Table Selection Dialog
The Filters page of the Table Options dialog form (Figure 9.9) is used to define conditions for selecting items to appear in a table. To filter the contents of a table:
- Use the controls at the top of the page to create a condition (e.g., Pressure Below 20).
- Click the Add button to add the condition to the list.
- Use the Delete button to remove a selected condition from the list.
Multiple conditions used to filter the table are connected by AND's. If a table has been filtered, a re-sizeable panel will appear at the bottom indicating how many items have satisfied the filter conditions.
Figure 9.9 Filters Page of the Table Selection Dialog
Once a table has been created you can add/delete columns or sort or filter its data:
In addition to graphs and tables, EPANET can generate several other specialized reports. These include:
- Status Report
- Energy Report
- Calibration Report
- Reaction Report
- Full Report
All of these reports can be printed, copied to a file, or copied to the Windows clipboard (the Full Report can only be saved to file.)
EPANET writes all error and warning messages generated during an analysis to a Status Report (see Figure 9.10). Additional information on when network objects change status is also written to this report if the Status Report option in the project's Hydraulics Options was set to Yes or Full. To view a status report on the most recently completed analysis select Report >> Status from the main menu.
Figure 9.10 Excerpt from a Status Report
EPANET can generate an Energy Report that displays statistics about the energy consumed by each pump and the cost of this energy usage over the duration of a simulation (see Figure 9.11). To generate an Energy Report select Report >> Energy from the main menu. The report has two tabbed pages. One displays energy usage by pump in a tabular format. The second compares a selected energy statistic between pumps using a bar chart.
Figure 9.11 Example Energy Report
A Calibration Report can show how well EPANET's simulated results match measurements taken from the system being modeled. To create a Calibration Report:
- First make sure that Calibration Data for the quantity being calibrated has been registered with the project (see Section 5.3).
- Select Report >> Calibration from the main menu.
- In the Calibration Report Options form that appears (see Figure 9.12):
- select a parameter to calibrate against
- select the measurement locations to use in the report
- Click OK to create the report.
After the report is created the Calibration Report Options form can be recalled to change report options by selecting Report >> Options or by clicking on the Standard Toolbar when the report is the current active window in EPANET’s workspace.
A sample Calibration Report is shown in Figure 9.13. It contains three tabbed pages: Statistics, Correlation Plot, and Mean Comparisons.
The Statistics page of a Calibration Report lists various error statistics between simulated and observed values at each measurement location and for the network as a whole. If a measured value at a location was taken at a time in-between the simulation's reporting time intervals then a simulated value for that time is found by interpolating between the simulated values at either end of the interval.
Figure 9.12 Calibration Report Options Dialog
Figure 9.13 Example Calibration Report
The statistics listed for each measurement location are:
- Number of observations
- Mean of the observed values
- Mean of the simulated values
- Mean absolute error between each observed and simulated value
- Root mean square error (square root of the mean of the squared errors between the observed and simulated values).
These statistics are also provided for the network as a whole (i.e., all measurements and model errors pooled together). Also listed is the correlation between means (correlation coefficient between the mean observed value and mean simulated value at each location).
Correlation Plot Page
The Correlation Plot page of a Calibration Report displays a scatter plot of the observed and simulated values for each measurement made at each location. Each location is assigned a different color in the plot. The closer that the points come to the 45-degree angle line on the plot the closer is the match between observed and simulated values.
Mean Comparisons Page
The Mean Comparisons page of a Calibration Report presents a bar chart that compares the mean observed and mean simulated value for a calibration parameter at each location where measurements were taken.
Reaction Report
A Reaction Report, available when modeling the fate of a reactive water quality constituent, graphically depicts the overall average reaction rates occurring throughout the network in the following locations:
- the bulk flow
- the pipe wall
- within storage tanks.
A pie chart shows what percent of the overall reaction rate is occurring in each location. The chart legend displays the average rates in mass units per hour. A footnote on the chart shows the inflow rate of the reactant into the system.
The information in the Reaction Report can show at a glance what mechanism is responsible for the majority of growth or decay of a substance in the network. For example, if one observes that most of the chlorine decay in a system is occurring in the storage tanks and not at the walls of the pipes then one might infer that a corrective strategy of pipe cleaning and replacement will have little effect in improving chlorine residuals.
A Graph Options dialog box can be called up to modify the appearance of the pie chart by selecting Report >> Options or by clicking on the Standard Toolbar, or by right-clicking anywhere on the chart.
Full Report
When the icon appears in the Run Status section of the Status Bar, a report of computed results for all nodes, links and time periods can be saved to file by selecting Full from the Report menu. This report, which can be viewed or printed outside of EPANET using any text editor or word processor, contains the following information:
- project title and notes
- a table listing the end nodes, length, and diameter of each link
- a table listing energy usage statistics for each pump
- a pair of tables for each time period listing computed values for each node (demand, head, pressure, and quality) and for each link (flow, velocity, headloss, and status).
This feature is useful mainly for documenting the final results of a network analysis on small to moderately sized networks (full report files for large networks analyzed over many time periods can easily consume dozens of megabytes of disk space). The other reporting tools described in this chapter are available for viewing computed results on a more selective basis.