## GREG1 : One Dimensional Problems

By “one dimensional data” we mean any distribution of (X,Y) data points. This obviously includes functions Y=f(X) and X=f(Y), but also more general cases. Plotting such kind of data is the simplest thing GREG can do. This can be done basically in four modes :

1. The broken line mode using command CONNECT, in which data points are simply connected by straight lines. Note that data must be ordered.
2. The curve mode using command CURVE, in which the data is interpolated to produce a smooth aspect. Again, the data must be adequately sorted.
3. The histogram mode using command HISTOGRAM. As above, data must be ordered. Note that this capability is restricted to functions Y=f(X).
4. The marker mode using command POINTS, in which a graphic marker is plotted at each data point. The size of the markers may depend on values in the Z buffer. Contrary to the other commands, the data need not be ordered at all.

In addition to these four commands, the command ERRORBAR which uses the Z buffer to define errors may also be relevant to one-dimensional data. A facility to sort data by ascending order is given by means of command SORT.

All these commands belong to the so-called “GREG1” language (in the SIC meaning) ; this language also includes all the utility functions of GREG such as pen definitions, annotations, coordinate conversions, etc...