#### Using xgraph to create bar and line graphs

(1) in an xgraph data file list some number of data sets (one per curve)
A data set contains an ordered pair of X Y coordinates, each point on
a separate line. The name of the data set can be specified by a line
begining with a double quote. Here is some sample data for ploting the
function f(x) = 2^x and f(x) = x^2:
"f(x) = 2^x
1 2
2 4
3 8
4 16
5 32
6 64
7 128
"f(x) = x^2
1 1
2 4
3 9
4 16
5 25
6 36
7 49
(2) To get xgraph to graph this data do:
xgraph data_file
(3) In addition, xgraph has all kinds of command line options for setting
the scale of the graph, for specifying titiles and lables...
try:
xgraph -bar -brw 0.5 data_file
xgraph -lny data_file # specifies logrithmic Y axis
xgraph -lx 4,6 -ly 16,50 data_file # zoom into part of the graph
look at the man page for more options