Running a network

Running a DX network to generate a visualisation comprises three stages: specifying the input (particularly the file to be read), running the network and examining the result. This example describes how to execute the simple network loaded in the previous section. It will be used to view an example data file, supplied with the cookbook, which contains a data cube of a simple Gaussian. This data cube is a `field' in the context of DX; see Section  for an explanation of this term.

1. Double-click on the `Import' module; the configuration window shown in Figure  should appear.
   1. Set input `name' to: $STARLINK_DIR/examples/sc2/field.general

      This file is the DX `header' file describing the data file. Files written by an external program and imported into DX are described by a separate header file. See Sections  and for details. Note that it is the name of the header file, not the data file, which is given here. If the header file is in your current directory then the directory specification can be omitted.

   2. Set input `variable' to: Gaussian

      This input specifies which field within the data file is to be read. In the current example the field is called `Gaussian'. Again see Sections  and for details.

   3. Set input `format' to: general

      Here `general' means that the data file has been written by an external program and is described by a separate header file. The only other option which you are likely to encounter is ` dx' for a native DX format file.

   4. When all the values have been set correctly simply click on the `OK' button.

2. To run the network select `Execute Once' from the `Execute' menu. The network will probably take a few minutes to run.

3. After a few minutes a window containing the visualisation will appear. The options for this window allow you a great deal of choice in viewing the visualisation. The following couple of hints might be useful.
   • DX is a bit lackadaisical about resetting the limits of the plot when a new visualisation is generated. If your visualisation does not neatly fill the plotting window (it may be either too big or too small) select the `Reset' option from the `Options' menu.

   • By default DX generates a view perpendicular to one of the axes, which gives an unnaturally `flat' appearance to the image. For a better perspective view select the `View Control' option from the `Options' menu. The `View Control' window appears. Set the `Set View' toggle to `Diagonal' or one of the `Off...' options.