| Developers' Corner

Inspection of variables

"Plot as Function" in HDevelop
"Plot as Function"
Inspect variables
Tabular view of control variables

Everyone knows the issue, when you have numeric tuples with many elements, and you are interested in a quick overview of their content. Since HALCON 12, a new feature has been available to visualize numeric tuples graphically. In the Variable View, it is now possible to plot tuples of numbers by selecting "Plot as Function" from the context menu. Multiple tuples can be inspected simultaneously in a single inspection window.

Additionally, a pair of tuples of matching length can be plotted as an x/y scatter plot. It is also possible to integrate these plots into your HDevelop code. This can be achieved by using the two operators

dev_inspect_ctrl (Var) 
dev_close_inspect_ctrl (Var)

and setting the parameter to 'tuple', 'plot' or 'plot_xY', depending on which inspection you are interested in.

Besides the quick graphical inspection, it is also possible to get a statistical overview of tuples. Firstly, inspect a tuple in the tabular viewer. On the bottom of this tabular view several statistical values are displayed, such as minimum value, maximum value, sum of values, mean value, deviation, value types, number of values and semantics (if appropriate). You can add and delete these values by clicking on the names of the values with the right mouse button.

Using the inspection tool, control variables, which belong to the semantic types, such as matrix, pose or frame grabber, can also be inspected quickly. In case of a pose, the elements can be assigned directly to the translations, rotations and type. The inspection of an acquisition handle is even more comfortable. The inspection opens a dialog with basic image acquisition device parameters. It also displays the name, image size, device, port, and other features of the image acquisition device.

The complete documentation to inspect control variables can be found in the HDevelop User's Guide in chapter "6.7 Inspecting Variables". A quick overview is given in our standard example program dev_inspect_ctrl.hdev.