Cause we are handling point data, it is always important to have a program to show the points in a graphical way. The progrm we suggest is the public domain programm xvgr or xmgr from Paul J. Turner. These toolbox programs are fully compatible with the data format of the xvgr-program. That means information stored in the datafile by the xvgr porgram will not be destroyed. Those informations are needed inside the xvgr program to specify the view of the data. Through the compatibility it is possibly, to take a file from xvgr, operate on it and the reread the changed data in xvgr again with having the same view as before.
The specifications of the view are given by keywords that start with a -@ symbol. In the following we will call those lines functions. Some functions are:
@title Hallo The title of the graph.
It is possible to add specific tools that react on these functions. In this way tools can be written to translate the xvgr format to any other representing programm.
xvgr also allows comments inside the data file. Comments begin with a -# symbol. In the tools we make extensive use of the comments: Informations generated by a tool are always printed as comments so they wouldn't cause an error when combined with other tools.
gr_analyze -f test.dat
It is thougth of using the functions and comments as a second way for controling the behaviour of the tools in the future.