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ABSTRACT
The mixed graph feature in ProVision is useful for combining traces from multiple files or the same file when the traces would not be graphed together. Mixed graphs are available in ProVision 1.60 build 4626 and subsequent releases. However, simply creating a mixed graph is only a small part of the versatility afforded by this new feature. This whitepaper serves as a demonstration of the additional functionality that is available when working with mixed graphs.
The typical method for generating a mixed graph is to use the trace mixer form via the individual files that contain the trace data to source the graph from. However, when necessary to compare multiple permutations of sets of files, this procedure can quickly become redundant and prone to error. Therefore, ProVision includes the option to save a previously-created mixed graph as a template.
SAVING A TEMPLATE
Once a mixed graph has been created, in order to save it as a template, simply select either the toolbar button, or, under the Tools menu, “Trace Mixer Template” as shown in Figure 1. This causes the prompt for the template title to appear as shown in Figure 2. The template title does not necessarily have to be the same as the original graph title, but the template title does replace the existing graph title. Select OK to confirm.
Figure 1. To save a mixed graph as a template, select “Trace Mixer Template” from the Tools menu
Figure 2. Prompt for template title
After the title is confirmed, this adds a new node to the Explorer Tree, attached to Graphs and Reports. The text of this new node is the title specified in the previous step. Whenever a mixed graph is created, it is done so using traces from a specific set of files. However, when a mixed graph is saved as a template, the references to these specific files are removed and only information about which traces to use remains.
LOADING A TEMPLATE
To load a mixed graph template, activate the checkboxes next to the files to be mixed in the explorer tree. Then, double-click with the mouse the node under Graphs and Reports that represents the template. This launches the File Selection Dialogue, as shown in Figure 3. An option is available for each unique file in the original mixed graph, and the options are initially populated with the checked files. If there are more options than files, then the selected files will be repeated to fill out the remaining options. Consequently, if there are more files selected than options, as many files will be listed as there are options available. The file associated with each option can be changed by selecting a new file for that option via the drop-down box.
Figure 3. File selection
After selecting OK, the mixed graph template is loaded accordingly and displayed, just as if it had been created using the trace mixer graph form. Note that mixed graphs can only ever be saved as templates, and not as a saved graph attached to a specific recording. This is due to the potential for the mixed graph to be generated from multiple files, and access to the multiple files is not always guaranteed. Any save operation on a mixed graph, aside from saving it as a template, will have no effect.
EDITING A TEMPLATE
Once a mixed graph is saved as a template, edits and modifications can be made to the template, although there are some limitations. To edit a template, first right-click the template node to be modified as shown in Figure 4. The resultant context menu contains entries for both “Edit with Graph Wizard …” and “Edit”. For this, select the latter entry: Edit. This launches the trace mixer form, repurposed as the graph template editor. It is also possible to modify the template using the “Edit with Graph Wizard …” option, though this is not recommended as the wizard does not permit the addition of new specific traces.
Figure 4. Mixer Context Menu
Note that if any new traces are to be added to the template, graphs must be opened which contain those traces. From here, the template can be reconfigured with new traces added and existing ones removed as shown in Figure 5. Note that existing traces already in the template have numbers next to them instead of filenames: the original filenames have already been stripped out at this point, such that only references remain. This means that it is not possible to correlate any new traces to the existing ones: new traces are appended to the graph. If it is necessary to correlate a new trace with an existing one, the only option is to recreate the mixed graph using the trace mixer form. To confirm the changes, select OK. The next time the mixed graph template is loaded, the changes will be visible.
Figure 5. Editing the graph template
SHARING A TEMPLATE
Once a template is created, it can be exported to exist independently of the instance of ProVision it was created on, such that it can be imported into another instance of ProVision. This process is similar to making a recording data file available to other users. To share a mixed graph template, right-click the template node to share and select the “Send by Email” option. From the resultant dialogue box, choose the radio button for “Save object to file you could send later:”, then select the Browse button. Doing so allows a filename and disk location to be specified for the exported file. Selecting OK archives the selected templates into the specified file. Once the file is created, it can be distributed in any number of ways, including being sent as an email attachment or placed on a network drive.
The exported archive contains a file with a .evm extension, which must be extracted from the archive prior to importing the template into ProVision. After the file is extracted, it can be imported by selecting the File menu in ProVision, followed by the Open option. From here, simply navigate to the folder containing the extracted file, highlight it, and select Open. ProVision will automatically parse the file, recognize the mixed graph template, and add it as a new node attached to Graphs and Reports. From here, the imported template can be used as though it were created natively.
A NOTE ON ZOOMING
Since mixed graphs are sourced from different files, not all of which necessarily have the same interval, zooming is handled uniquely for mixed graphs. While the procedure is unchanged—simply hold down the mouse button, and drag with the mouse across the section of graph to zoom into—the way the resultant data are displayed is slightly different. For example, compare the traces in Figure 6– for the lower one, the points are farther apart than the upper. This is due to the difference in the intervals. The upper trace in red has an interval time of one second while the lower trace in blue has an interval time of thirty seconds. Therefore, the red trace has thirty points between each set of points on the blue trace. This is important to remember when zooming, as the data are being displayed correctly, though in a different context from graphs where all the traces have the same intervals.
Figure 6. Zoomed traces showing different intervals
CONCLUSION
Being able to save and reuse a mixed graph as a template can streamline the process of examining the same trace data from multiple permutations of files, as recreating the graph each time can quickly become redundant. Using templates in ProVision is yet another way of simplifying the tasks of comparing multiple traces, especially when those traces are sourced from multiple files. Furthermore, being able to save and redistribute a mixed graph template ensures consistency.
Power Monitors Inc.
(800) 296-4120
theengineers@powermonitors.com
http://www.powermonitors.com
