When working with an XY plot or bar chart plot, you can enable units in your current HyperWorks Desktop session.  To enable units, go to the Preferences > Options panel and select Enable Unit Scaling.  You can also access the Options panel by selecting the Options button, , from the toolbar.

Once units are enabled, certain unit dialogs are displayed in HyperGraph depending upon the loaded file type and whether or not the file contains metadata.

You can more easily use the Convert Units dialog to convert the current units of measure when units are enabled.  When you enable units, less unit labeling is required in the HyperWorks Desktop session.

After assigning unit types and units to a file, reader or solver, these settings are stored in the current session and any subsequent sessions.  To reset these file allocations, use the Tools > Reset Unit Assocations dialog.

If plotted curves have units enabled and you plot a second curve with a different unit type, HyperGraph automatically generates a secondary axis for this curve and associates it to this axis.  Additionally, if you have a curve where units are enabled and you apply math or a function to a curve, HyperGraph retains the unit and unit type if the math and function do not affect the unit information.  If the math applied changes the unit type and/or the units, HyperGraph adds a secondary axis for this new curve.  An example of this is having a curve with the acceleration unit type and taking the integral of this curve to get the velocity.  This changes the unit type and units of the curve, so if other curves are in the plot, HyperGraph adds a secondary axis for the new unit type.  From the Units Profile and Select File Unit dialogs, click OK to set the default setting for units to None.  This results in disabling units on the applied curve.

Automatic Unit Recognition – When a file contains unit metadata, HyperGraph reads the metadata directly from the file, so you do not have to manually define the units.

Supported file types include:

Units Profile Dialog – When a file does not contain unit metadata, use the Units Profile dialog to select and enable a pre-defined unit system for the file so that the units do not have to be defined every time more data is plotted.

Supported files types include:

The Units Profile dialog is automatically displayed when these files are used.

Note        The Show Units Dialog check box on the Options panel does not need to be activated for the Units Profile dialog to be automatically displayed.

Units Profile dialog.

Unit Support for Math Functions

Beginning in HyperGraph 14.0, unit-sensitive math functions in HyperGraph can handle unit conversions internally, without any user-defined scaling or modification required.  Prior to HyperGraph 14.0, if a unit-sensitive math function was used, and the units for the associated axis are changed, you were required to manually update scaling factors to obtain the correct values from the math function.  Unit handling is also available for user-defined Templex functions, so that you can set the unit expectations for the registered Templex functions.  This allows you to specify the expected units for a function’s unit-dependent arguments, and any necessary conversion for the unit-dependent arguments that are not in the expected units occurs automatically in sessions when units are enabled.

The units setting (whether enabled or disabled) applies to the entire session.  In other words, the unit handling is either enabled or disabled for every curve in the session; sessions with mixed units settings (units enabled for some plots and not for other plots) are not allowed.

In the image below, units are not enabled for the selected curve.   After loading the curve, select a vehicle safety tool (VST) function such as clip from the Injury menu.  Without units enabled, you must manually enter the scaling factors in the Timv conv. and Accel conv. fields so that the curve fits properly.

Unit scaling not enabled; scale factors entered.

However, with units enabled, and with the same curve and VST function selected, there is no need to manually adjust the scaling factors; the scaling is applied automatically.  Notice in the image below, the Time conv. and Accel conv. fields are no longer there.

With units enabled, you can also use the Convert Units context-sensitive menu to change the axes values from ms to s for the Time axes in the image below, or from m/s2 to gravities for the Linear Acceleration axis below.  Doing this does not affect the values as shown in the curve note shown in this image; they will remain the same

Unit scaling enabled.  No longer necessary to manually enter scaling factors.

If units are not enabled and you return to the Options panel to enable them, the HyperGraph session will restart.  The message shown below is displayed.  Click Yes to restart the session with units enabled.

Legacy Data

It is possible to load a legacy session file or report template file with units disabled into HyperGraph when units are enabled.  Upon loading, a error message dialog is displayed, listing errors related to the math functions contained in your session file and how the functions are currently supported.  You can update your session accordingly and save it as a new session to be loaded at a later time, without the error messages.

Select File Unit Dialog – For a file with a recognized unit system, use the Select File Unit dialog to set the data types to a known unit type.  Set the atomic units (length, mass, time, temperature, and angle) to a unit system.

Supported file types include:

Select File Unit dialog

Enable/Change Curve Units Dialog

From the Enable/Change Curve Units dialog, you can change the unit type and measurement of a curve.

To view the dialog, select a curve from the plot window and right-click.  From the context sensitive menu, select Enable/Change Curve Units.

Enable/Change Curve Unit... context sensitive menu option

For the X Vector and Y Vector, select a new unit type from the drop-down menus.  To disable a units for a vector, select None.

Enable/Change Curve Units dialog

Reset Units

To reset the units for a file, select Tools > Reset Unit Association.  From the dialog, select a filename from the list and click Reset Units.

Reset Units Association dialog