7 Interfacing issues Here we explain the main mechanisms to communicate with other programsand data files from Tela. How to extend Tela by your own C/C++functions has been explained in the previous section.

There are three principal mechanisms to use Tela together with Matlab.

You can import and export Matlab binary files to and from Tela using the import, import1, export_matlab commands. Also Matlab-readable plain ASCII files can be read by import1. Even all your workspace variables can be exported or imported easily in binary form. That is, Tela has the same functionality as two separate Matlab processes would have.

It is possible to translate your Matlab scripts and M-files to Tela language. A translator program m2t exists for this purpose. See man m2t for details.

If you have the matlabeng.ct module linked within Tela, you can call Matlab functions and evaluate strings as Matlab commands at run time. To enable this, there is function matlab_start, which starts Matlab in the background and sets up necessary communication links. This is a good aid in development phase if e.g. some important function is missing in Tela. You can borrow it from Matlab.

Tela's native binary format is the HDF (Hierarchical Data Format from Univ. Illinois/NCSA) format. HDF files created with the save command can be read by various programs supporting HDF, for example Spyglass tool programs and IDL. The import command can also read many other types of HDF files meaningfully. The function export_RIS8 exports 8-bit raster image sets in HDF format.

Generic ASCII files can be read by the import1 command. Multidimensional datasets can also be read by inserting the size information on the first line in a simple format (see help import1). ASCII files can be written using the fformat and fprintf functions.

The PlotMTV program is responsible for the graphics. It will save the image in PostScript file if you click the appropriate button. In PlotMTV1.4.1t and later you can also save the image as a GIF (Graphics Interchange Format) file by pressing another button. When the main PlotMTV window has been divided in several data windows, pressing the GIF button will include all data windows in the file. Pressing Shift-G under these circumstances will include only the current data window. The GIF saving will work properly only if the whole window is visible on your workstation screen (or in the virtual screen, i.e. it must be in video-RAM).