Characteristics

Many aspects of the EXTREMA program are controlled by setting the values of program characteristics. For example, the length of the x-axis tic marks are controlled by the `XLARGETICLENGTH` and `XSMALLTICLENGTH` characteristics. These characteristic values are changed with the `SET` command, and obtained with the `GET` command.

General characteristics
Graph legend characteristics
File related characteristics
Data curve and plotting symbol characteristics
x-axis characteristics
y-axis characteristics
Polar axis characteristics
Text related characteristics