Using Vertical Axis Groups to Plot Signals of Different Scales or Units

LabOne^® offers a flexible display of multiple signal waves within the same plot. This blog post describes the functionality of the vertical axis groups, which make it possible to finely control how signals are bound together within the plot. Vertical axis groups are available in the Plotter tab, SW Trigger tab and Sweeper tab. These tools are able to show signals with different axis properties within the same plot. As frequency and amplitude axes have fundamentally different limits, they have each an individual axis that allows for correct auto-scaling. However, signals of the same type such as Cartesian demodulator results should preferably share one scaling to enable fast signal strength comparison. To achieve this, the signals are assigned to a specific axis group. Each axis group has its own axis system; this default behavior can be changed by moving one or more signals into a new group. All vertical axis groups share the same horizontal axis.

The tick labels of only one axis group can be shown at once. This is the foreground axis group. To define the foreground group, click on one of the group names in the Vertical Axis Groups box. The current foreground group gets a high-contrast color. If a group is empty, the selection is not performed. Axis properties like mapping and scaling are handled per group.

Selecting the active signal

The active signal is placed at the front and gets a high-contrast color. Newly added cursor math statistics will be based on the active signal at the time of adding. The active signal also defines the foreground group. A change of the active signal can also be performed by clicking on the signals in the legend inside the plot.

Splitting the default vertical axis group

Use drag & drop to move one signal on the field [Drop signal here to add a new group]. This signal now has its own axis system. The splitting of signals into different groups is helpful if the signal strength is very different.

Changing the vertical axis group of a signal

Use drag & drop to move a signal from one group into another group that has the same units.

If the signal does not have the same units as the target signal group, the mismatch is indicated and the merge is not executed.

Group separation

In case a group hosts multiple signals and the units of some of these signals change, the group is split in several groups according to the new units.

Removing a signal from the group

To remove a signal from a group, drag & drop the signal to a free area inside the Vertical Axis Groups box.

Removing a vertical axis group

A group is removed as soon as the last signal of a custom group is removed. Default groups remain active until they are explicitly removed by drag & drop. If a new signal is added that matches the group properties, it is added again to this default group. This ensures that settings of default groups are not lost, unless explicitly removed.

Renaming a vertical axis group

New groups get the default name "Group of ...". This name can be changed by double-clicking on the group name.

Hiding or showing a signal

Uncheck or check the check box of the signal. This is faster than fetching a signal from a tree again.

Acknowledgments: Many thanks to Jürg Schwizer for preparing this blog post.