Getting Started Manual
Tecplot Chorus 2024 Release 1

The Properties panel in the Tecplot Chorus sidebar lets you choose the options for the Matrix View. You’ll probably find this at the left of the Tecplot Chorus workspace. If the Properties panel is not already open, choose View → Properties to open it.

Each open view or plot has its own properties, even if the views are of the same type. If you have more than one Matrix View open, for example, each Matrix View has its own properties, which are completely independent of any other Matrix View’s properties.

If you explore the Matrix View Properties for a few moments, you will discover:

To review: Tecplot Chorus chooses thumbnails based on the variables you’ve chosen for the rows, columns, and optionally pages of the matrix. If multiple cases match these variables and have images, Tecplot Chorus chooses a representative case for the actual thumbnail display. You can turn on labels in the sidebar to see the value of unused variables, and you can use filtering to indirectly choose these values. We won’t talk about filtering in detail this lesson, but you might want to give it a try in the Filters sidebar.

The 3D Scatter Plot, arguably the snazziest plot in Tecplot Chorus, is accessed by clicking on the toolbar or by choosing View → New 3D Scatter Plot.

Each sphere in the scatter plot represents a single case in your project. Since this is 3D, let’s have some fun rotating it! Click the Rotate icon in the Toolbar and then click and drag in the plot window. Viewing your data from a new angle literally gives you a new perspective on it.

In the Properties sidebar, you’ll see many options for changing the appearance of your scatter plot. (For now, ignore the options for under the heading Surrogate Model.) In particular, we’d like to draw your attention to the following:

Remember earlier when we mentioned that you can open multiple instances of any plot or view, each with its own properties? Give that a try too: open two 3D Scatter Plots, rotate them differently, and give each its own axis settings and visual look using the Properties panel.

It’s important to note that you can select cases in a scatter plot. So it’s not just a plot; it’s also another way into the cases in your project! (All the Tecplot Chorus plots work this way.) Choose the Select tool on the toolbar, then click a few of the spheres or cubes. Hold down Control while clicking to select multiple cases, or drag out a rectangle around a group of cases that you want to select.

Once you’ve selected a case or six, click the right mouse button. You’ll see that you have the same options here for viewing images or data that we talked about when we were discussing Matrix Views. Go ahead and try them out, if you like, just to confirm that they work the same.

The 2D scatter plot is similar to the 3D one we’ve already described, just flatter. You only get to specify variables for the X and Y axes, and of course you can determine the color and size of the scatter symbols by a variable, if you like.

An interesting 2D Scatter Plot to make with our example project has Alpha and Lift Coef. on the X and Y axes, respectively, and is colored using the # Iterations variable. Add a legend and position it out of the way of the data. The resulting plot reveals that Alpha has a nearly linear positive effect on lift, and also that most of the cases took 200-250 iterations for the solution to converge.

Switch the X-Axis variable to Beta, and it is clear that Beta’s relationship to lift is more complicated.

Plotting one dependent variable against another can reveal correlations. Here’s a plot of lift vs. drag (colored by Mach No.) revealing that at a given Mach No., lift and drag have a seemingly quadratic positive relationship:

As with the 3D Scatter Plot, you can select cases in your 2D Scatter Plot to view their images or data using the Select tool. Give it a try, clicking with and without the Control key and dragging rectangles around cases. Then right-click and view the images or data associated with the selected cases.

If you’ve been playing with the filters, and have set coloring to "Color by Filter Violations," you may see shading on the plot. This visualizes the effect of the filters active for the axis variables. The individual cases are colored according to how many filters they violate (see the legend for the details).

Tecplot Chorus’s Line Plot ( button or View → New Line Plot) is actually three plots in one, because it can display a symbol for each case, lines connecting the cases, or both symbols and lines.

Although, on the surface, it has less "wow" factor than, say, the 3D Scatter Plot, the humble line plot is a versatile tool for communicating results. Why not follow along and try to reproduce our plot? The controls are not unlike the ones we’ve already seen for the other plots,. As with the 3D Scatter Plot, just ignore the Surrogate Model section in the Properties panel for now.

In addition to the axes, you can also choose to use color and/or symbol shapes to represent up to two additional variables. Using a variable for color or symbol causes each discrete value of that variable to be drawn as its own line (if lines are active), using its own color or symbol shape respectively.

Can you find the exact settings we used for that plot?

Answer: X-Axis: Mach No. Y-Axis: Lift Coef. Show Lines. Sort By: Mach No. Color: By Variable/Alpha. Symbol: Shape/Circle. Symbol Size: 1.

As always, you can select cases and view images or data for them. By now, that should be old hat. We’ll just note here that turning on symbols in a line plot is very handy for figuring out where the cases actually are on otherwise smooth, featureless lines.

First, launch the Tecplot Chorus application, for example by double-clicking the shortcut on the Windows desktop that was created during installation. (Linux users should just be able to type chorus in a terminal window.)

Choose Open CSV Project from the File menu in Tecplot Chorus. This is the simplest way to create a new Tecplot Chorus project, and our CSV file is perfectly formatted to work with it.

If we needed to use delimiters other than commas, or we needed to specify variable natures because our CSV file didn’t have a second header row, rest assured that Tecplot Chorus can deal with those kinds of files too.

Using the Select Delimited Text Metadata File dialog, choose the file plume_input.csv in the Plume folder and click the Open button.

Tecplot Chorus creates a new project from the CSV file. The project’s database file, plume_input.chprj, is created in the same folder as the CSV file and given the same base name. After creating the project file, Tecplot Chorus automatically opens a Table View, as shown here.

You can see all 16 cases and, with a little horizontal scrolling, all of the fields for each case. Note that the FileName field is not displayed; instead, this field is used to link each case to its data file. It will be used when opening the data files for individual cases.

First, right-click the first case (Case ID 1) in the Table View, then choose View Data from the context menu.

The View Data dialog appears.

Click OK without changing anything in this dialog to view the case’s data. Tecplot 360 opens and displays the data file.

Now working in Tecplot 360, we’ll zoom and rotate the view to reveal two building structures with an exhaust port on top.

First, let’s zoom in. You can do this using the Zoom tool on the Tecplot 360 toolbar, but a quicker way is to hold the Control key on the keyboard, hold down the middle button or wheel on your mouse, and drag the mouse up and down to zoom in or out around the center of the plot. Zoom in so you can see the buildings, as shown below (your result needn’t be exactly like this).

Now let’s rotate the plot so the buildings are right-side-up and we can easily see the exhaust port. Place the mouse pointer in between these two boxes (don’t click!) and press the O key on your keyboard to set the center of rotation. Now, when we rotate the plot, it will rotate around that point. This will help keep our image on the screen instead of being rotated off of it.

Tecplot 360 has several tools for rotation on its toolbar. The Rollerball rotation tool is most commonly used, so it has a shortcut: simply hold the Control key on the keyboard, hold the right mouse button down, and move the mouse. (If you have a 3D mouse attached to your computer, you can also use that.)

As you rotate, you may find that the buildings are no longer centered (or may even be partially off the screen) and you need to move the plot. You can do this using the Translate (a.k.a. Move) tool on the toolbar. Again, this is such a frequently-used tool, there’s a shortcut for it: simply click and hold the right mouse button and drag the plot to where you want it.

By zooming, rotating, and translating the plot, you should be able to get the Y axis pointing straight up and the rest of the plot oriented approximately as shown below.

As you rotate the plot, you will see a dot on top of the smaller building. That’s the exhaust port, visible in the above screen shot.

We’ll now add a slice right through the air above the exhaust port to show the concentration of SO₂ along a plane.

First, activate the Slices checkbox in the Derived Objects section of the Tecplot 360 Plot sidebar, as shown here.

The slice appears in the plot, initially contour-colored by pressure.

Next, click the Slice button next to the Slices checkbox to activate the Slice tool. Then drag the slice so it goes through the exhaust port .

Now, open the Contour & Multi-Coloring Details dialog by choosing Contour/Multi-Coloring from the Plot menu.

In this dialog, use the menu at the top to set the variable to so2. (Leave the dialog open.) The plot should now look something like this:

Let’s zoom in and reposition the plot, using the same tools we used before, to focus more on the exhaust port and to avoid clutter behind the legend. Your plot should now be in this ballpark:

Finally, use the Add Contour Level tool in the toolbar to add additional contour levels near the port. This will increase the number of contour levels you can differentiate. Just click a few places to the left of the port to see how the tool adds contour levels. (The new contour levels are also visible in the Contour & Multi-Coloring Details dialog.)

Your plot should look something like this:

You can now close the Contour & Multi-Coloring Details dialog.

A style template is a Tecplot 360 instruction file that records the visual appearance of a plot, but contains none of its data. This will allow us to easily make plots for the other cases in the study, all with the same general appearance.

To save a style template, just click the Save Style Template button in the Chorus sidebar at the right of the plot. Then use the Write Style File dialog to specify a name for the file (for example, "XSlice") and save it.

We can use the style template we just created to help us compare multiple cases. When we open the data files, we have the opportunity to specify the style template, which will then be applied to each data file as it is opened in Tecplot 360.

Leave the Tecplot 360 window open, but bring the Tecplot Chorus window back to the front and highlight case ID 15 in the Table View. Right-click and again choose View Data using the context menu.

The View Data dialog appears. Click the XSlice.sty template from the drop-down menu, then click OK.

Tecplot 360 now opens case 15 in a new page and applies the style template. You will see both cases listed in the View Page section of the Tecplot Chorus sidebar and can easily flip between them.

Let’s add a label to the plots showing the input variables, so it is easier to see which case we’re viewing. To do this, select the South East (mph), North East (mph), and Mass Fraction of SO2 variables in the Label Frames section of the Tecplot Chorus sidebar.

The resulting plot looks like this:

When you open cases one at a time from Tecplot Chorus, each appears on its own page in Tecplot 360. When you open multiple cases at once, they all appear on the same Tecplot 360 page.

To see this in action, return to Tecplot Chorus and select the first three cases in the Table View. Then right-click them and choose View Data as before. In the View Data dialog, make sure the style template you created is still active, then click OK.

The following plot appears in Tecplot 360. Each case you selected in Chorus is in its own frame.

Try zooming and panning (translating) the view of any frame using the Zoom and Translate tools. You’ll see that all frames zoom and move together.

However, any style changes you make in one frame (for example, changing the contour coloring) are not applied to the other frames, because you may want to make style changes in order to highlight aspects of a particular plot. If you want to apply your style changes to all frames, click Synchronize Styles in the Tecplot Chorus sidebar (within Tecplot 360) after making the changes. This function copies the style from the active frame to all frames.

Tecplot Chorus can show you, visually, the differences between a master case and additional cases you are viewing.

To create a data difference plot, first click in the frame you wish to designate as the master and click the Set Current Frame as Master button at the bottom of the Tecplot Chorus sidebar (inside Tecplot 360).

Try it now, designating the middle frame of the three as the master frame. After choosing the master, you can then activate the Show Diff Data checkbox.

Tecplot 360 displays an additional frame below the non-master frames with the differences between those frames and the master, as seen here.

The values of all data in the difference frames are the result of subtracting their data from the master frame’s data, creating a new variable. Since the values of this variable will likely have very different values from the originals, you may wish to choose a different color map for the difference frames.

Tecplot 360 includes diverging color maps that are one color in the middle and shades of two other colors toward the extremes. This allows you to easily color, for example, areas that are the same white, areas where the difference is positive red, and areas where the difference is negative blue.

To use one of these color maps:

The resulting plot may look like this:

You can also generate images using your saved style template, essentially pre-rendering a particular view of the data for some or all of the cases in the study.

Especially when working with large data sets, viewing an image you have already created from the data can be much faster than opening the data itself. And you can also use the images as thumbnails to organize and access the cases visually using Tecplot Chorus’s Matrix View.

Let’s go ahead and generate images for all our cases using the XSlice style template. To do this, highlight all cases in the Tecplot Chorus Table View (there’s a handy keyboard shortcut: Control-A for Select All). Then right-click and choose Create Images.

The Create Images dialog appears. In this dialog, make sure XStyle is selected as the style template and click OK.

Tecplot Chorus instructs Tecplot 360 to load each data file, apply the style template, and save a PNG image file. This happens in the background, and you can continue using either product while the operation is underway. When all the images have been generated, a green dot in the Manage Jobs button at the bottom of the Tecplot Chorus window indicates that the background job is complete and the results may be deposited.

When you click Manage Jobs, the Manage Jobs dialog appears.

In the Manage Jobs dialog, you can select any background job whose status is Ready, then click Deposit, to add the images to your project. The Append Data wizard appears, asking us how we want the new images tagged.

In this case we have modified the default tag FileName-XSlice (a name generated from the fact that the data file is tagged FileName based on the column name of the original CSV file, and the style template applied was XSlice) to just be XSlice. We don’t have more than one data file for each of our cases, so including it in the tag is redundant. Click Next to proceed to the final screen of the Append Data wizard, then click Finish to complete the deposit operation.

Additional style templates are included in this tutorial’s download. These include:

Give them a shot with the View Data or Create Images functions.

The Matrix View is a grid of images where the meaning of rows and the columns is based on the metadata variables in the project. To open a Matrix View, click on the Tecplot Chorus toolbar, or choose New Matrix View from the View menu. An example is shown below.

In this example, we’ve put the South East wind speed variable on rows and the North East wind speed variable on columns. Each image in each row represents one or more cases having a particular value for South East (mph), and similarly for columns and North East (mph). If there are no cases having certain values for these variables, blank cells appear in the matrix.

A zoom slider is available at the bottom right of the Matrix View so you can decide how many cases you want to see at a time, or conversely, how much detail you want to see.

A small badge appears on each image here because there are multiple images having the indicated values (but with differing values of the third independent variable in our study). Change Page By to Mass Fraction of SO2, and the Matrix View instead will have a separate page for each value of this variable, which you can choose using the slider in the sidebar. This provides you a way to flip through the available values of a simulation input and see the impact it has on your results in an animated fashion. Try it out!

Also cast an eye on the Selected Image Values section of the sidebar as you click various cells of the Matrix.

You can learn much more about the Matrix View in the Tecplot Chorus User’s Manual. For now, change Page By back to None to return to the view we started with.

Right-click the top-left image in the Matrix View and choose View Images. The Selected Image View appears, showing you all the images that were "stacked" in that cell of the matrix because they share the same values of the row and column variables (that is, they all have both South East (mph) of 5 and North East (mph) of 5, but different values of Mass Fraction of SO2).

You can also select multiple cells in the Matrix Viewer to view all the images that those cells contain, or select cases in the List View, to view the images associated with those cases. You can open any number of Selected Image View windows, each with images from different cases (and other settings).

Every image in the Selected Image View represents one case. You can see the variable values for the selected case in the sidebar just as with the Matrix View. Again, you can read more about this view in the Tecplot Chorus User’s Manual.

When the Selected Image View is open, you can select an image to designate it as the master, then click the Diff From Current button in the Properties sidebar to display difference images. Here, we’ve selected the first image in the Selected Image View we opened in the last step as the master.

The image difference window is similar to the data difference display we previously saw, only it works with the rendered images rather than the raw data. It is not as accurate as comparing the actual data, nor as interactive, but it is much faster given that the images already exist, and it can give you a quick idea of what areas of your data are changing from case to case. You can then investigate these differences further by comparing the actual data of selected cases.

Return to Tecplot Chorus, select any case in the Table View, right-click, and choose View Data from the context menu. Choose None for the Style Template in the View Data dialog, then click OK. The case’s data file opens in Tecplot 360. Now you’re ready to record a macro of the integration. To do this:

Now you’re ready to apply that macro to all our cases and import the result into the project.

Return to the Tecplot Chorus application, select all cases in the Table View (keyboard shortcut: Control-A), right-click, and choose Extract Variables from the context menu. The Extract Variables dialog appears.

Choose the groundSO2.mcr macro file you just created from the Macro drop-down menu, then click OK.

Tecplot Chorus schedules the extraction as a background job, much as when we generated images for all our cases. You can go on using Tecplot Chorus and/or Tecplot 360 while it finishes. When a green dot appears in the Manage Jobs button at the bottom of the Tecplot Chorus workspace, click it, then select the Extract Variables job and click Deposit. The Append Data dialog appears.

This dialog displays all the auxiliary data values available for each individual case. We only want one, so we’ll turn off the rest.

We want to use a more specific name for our new variable within Tecplot Chorus, so in the Display Name column, we’ll enter GroundSO2.

Now simply click the Finish button. You can now see that the new variable is visible in the Table View of your project.

The 3D Scatter Plot lets you view up to three dependent variables (typically one main variable and one or two less important ones) against two independent variables. To set up our scatter plot:

Leave the other settings at their defaults and ignore the Surrogate Model settings for now.

The plot should look something like this:

Click the Rotate tool in the toolbar and drag around in the 3D Scatter Plot window to change the viewing angle. You can get a sense of its depth, but since the data is so sparse it’s hard to understand what its shape might be. That’s where a surrogate model can help.

With the 3D Scatter Plot window active, click the Training button in the Surrogate Model section of the Properties sidebar. The Surrogate Model Training dialog appears.

In this dialog, you tell Tecplot Chorus which type of surrogate model you want (we will use a Quadratic Response Surface) and which independent variables you would like the model to include (in this case, the two independent variables we are using as axes in the plot).

Since there are just sixteen cases, it takes only a second to train the model. It will take longer in studies where there are more cases and/or more variables to consider.

In the Surrogate Model section of the Properties sidebar, click the Show checkbox to reveal the surrogate model. The surrogate model appears on the plot as a translucent, light blue surface, as shown here.

Take note of the R2 value displayed in the sidebar. This value, which is quite close to 1, indicates an extremely good fit.

The North East (mph) and Mass Fraction of SO2 variables of each case shown on the plot are inputs to our surrogate models. But our third dependent variable, South East (mph), is not used on our plot. What value of this variable is used in the Surrogate Model in this case? We can determine this by setting the evaluation point.

Right-click one of the points on the plot and choose Set Surrogate Model Evaluation Point. The Surrogate Model Evaluation Point dialog appears.

This dialog lets us set a value for each independent variable, which will be used when that variable is not being used on the plot. In this case only South East (mph) is not being used on the current plot, so only changes to that variable will affect the surrogate model. Move the slider and see how the surrogate model moves in response, then put it back down to the minimum value and close the dialog.

Using the rotate tool, have a look at the plot from different angles. What can we tell about the likely physical behavior of our facility based on the surrogate model?

These results seem reasonable and match our expectations.

Change the Z-axis to the variable downwind 25 (which represents the SO₂ concentration at a sampling point 25 yards downwind). Notice anything unusual? You may have to rotate the plot to see it.

We could expect all the cases to exhibit a near-linear relationship between both input variables and the downwind concentration of SO₂, and this is borne out by the nearly flat surrogate model surface. However, that one point is an outlier.

Let’s have a look at that case in Tecplot 360.

Try seeding some streamtraces around the slice plane, creating a new style template with the streamtraces.

Save a new style template and create new images for all the cases to help reveal what’s different about this case. Except for the streamtraces, you’ve done all of that before in this tutorial.

You may decide that this specific case is not representative and decide to exclude the outlier from the study. Right-click the offending dot in the 3D Scatter Plot, then choose Mark as Inactive from the context menu. The renegade will disappear from all plots and will no longer be considered by the surrogate model.

You can still find the case in the Table View, where a new column called Case Status has been created and the case (number 14) has been marked Inactive.

You can tick the Use Filters checkbox in the Table View’s Properties sidebar to hide the inactive case even in the Table View, or use the Case Status filter at the bottom of the Filters sidebar to show the case in all views even though it’s inactive.

For more information on filters, see the Tecplot Chorus User’s Manual.

Let’s open the CSV in Microsoft Excel and see what we’ve got.

Above we see just a small part of the data set (the full CSV file contains 866 rows in total). Looking at the first and second rows, we see they are the normal CSV file header bearing the name of each field, and the optional Tecplot Chorus-specific header indicating the nature of each field, leaving 864 rows representing the cases in the study. From the header rows, we can tell we have:

Now launch Tecplot Chorus and open the project. Open the provided CSV file in Tecplot Chorus by choosing Open CSV Project from the File menu. A corresponding .chprj (Chorus Project) file is created in the same directory as the .csv file. The .chprj file will be updated as you add new data to the project, so you should open it instead of the .csv file in the future.

Tecplot Chorus opens the Table View of the data.

You can see that the project contains the 864 cases we found in the CSV file, with all of the independent and dependent variables. Only the contours column, which contains the name of each case’s linked image, isn’t shown in the table; Tecplot Chorus uses it internally when viewing images. We can also see that a Case ID has been assigned to each case.

Tecplot Chorus’s Matrix View can help us visually understand what the independent variables represent and get a feel for how the inputs to the simulation might be affecting the results. Open a Matrix View from the Tecplot Chorus View menu or by clicking the Matrix View button on the toolbar.

Next, set up the Matrix View using the Properties panel, which is docked to the left side of the Tecplot Chorus workspace by default.

Using the Zoom slider at the lower right corner of the Matrix View, adjust the size of the individual thumbnails so you can see twenty or so cases.

Use the Page By slider to flip through the values of X in the project. As you move the slider, the thumbnails in the Matrix View change. This flipbook-style animation should make it immediately clear that the independent variable X represents the width of the actuator.

Scrolling vertically or horizontally will similarly show you how Y and Z affect the design. Y is the height of the actuator. An increase in Z correlates with an increase in the strength of the magnetic field, which means Z is the depth or thickness of the actuator’s design: it fits with what we know about X and Y, and also fits with Z’s effect on the dependent variables.

You may also notice a trend of color changes in the thumbnails as the independent variables change. Looks like there’s a legend on the images; let’s take a look! Right-click any thumbnail and choose View Images from the context menu. The Selected Image View window appears with the image from the selected case. Adjust the Zoom slider in this window so you can get a good look at the legend.

From the legend, we can see that red is associated with the strongest magnetic fields. So, generally speaking, the more red you see in an image, the stronger the magnetic field of that design. With that knowledge, you can close the Selected Image View window and flip through the thumbnails in the Matrix View to get a quick sense of how strong a magnetic field is generated by each actuator design and how each input variable affects this characteristic.

Finally, observe that we can see nine rows of eight cases, or 72 cases in total, in each page of the Matrix View. Dividing the total number of cases in the project, 864, by 72 gives us a nice round 12, which strongly implies that we have a case for every combination of the discrete values of all of our parameters: this is not a "sparse" project; there are no "missing" or unsimulated cases.

So set the zoom so you can see all 72 cases in each page, then flip through X using the Page By slider. You can quickly and easily verify that all cases have a thumbnail and that there are twelve discrete values of X used in the study.

We’ve learned an awful lot about our data set just using the Matrix View! But we can’t find out which cases satisfy our design goals using this view alone.