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 describes the functionality of the vertical axis groups which allow a fine control on 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 a frequency and amplitude axis have fundamentally different limits they have each their individual axis which allows for correct auto scaling. However, signals of the same type, e.g. Cartesian demodulator results, should preferably share one scaling. This allows for fast signal strength comparison. To achieve this the signals are assigned to 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.

 

1

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 will be handled per group.

Select 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 will also define the foreground group. A change of the active signal can also be performed by clicking on the signals in the legend inside the plot.

Split the default vertical axis group

2

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

Change vertical axis group of a signal

3

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

4

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

5

In case a group hosts multiple signals and the units of some of these signals changes, the group will be split in several groups according to the different new units.

Remove a signal from the group

6

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

Remove a vertical axis group

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

Rename a vertical axis group

New groups get a default name ‘Group of …’. This name can be changed by double-clicking on the group name.

Hide/show a signal

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

Acknowledgments

Thanks to Jürg Schwizer for preparing this blog post.