term% cat index.txt GRAPH(1) General Commands Manual GRAPH(1)
NAME
graph - draw a graph
SYNOPSIS
graph [ option ] ...
spline [ option ] ...
DESCRIPTION
Graph with no options takes pairs of numbers from the standard input as
abscissas (x-values) and ordinates (y-values) of a graph. Successive
points are connected by straight lines. The graph is encoded on the
standard output for display by the plot(1) filters.
If the ordinate of a point is followed by a nonnumeric string, that
string is printed as a label beginning on the point. Labels may be
surrounded with quotes "...", in which case they may be empty or con‐
tain blanks and numbers; labels never contain newlines.
The following options are recognized, each as a separate argument.
-a Supply abscissas automatically; no x-values appear in the input.
Spacing is given by the next argument (default 1). A second op‐
tional argument is the starting point for automatic abscissas
(default 0, or 1 with a log scale in x, or the lower limit given
by -x).
-b Break (disconnect) the graph after each label in the input.
-c Character string given by next argument is default label for
each point.
-g Next argument is grid style, 0 no grid, 1 frame with ticks, 2
full grid (default).
-l Next argument is a legend to title the graph. Grid ranges are
automatically printed as part of the title unless a -s option is
present.
-m Next argument is mode (style) of connecting lines: 0 discon‐
nected, 1 connected. Some devices give distinguishable line
styles for other small integers. Mode -1 (default) begins with
style 1 amd rotates styles for successive curves under option
-o.
-o (Overlay.) The ordinates for n superposed curves appear in the
input with each abscissa value. The next argument is n.
-s Save screen; no new page for this graph.
-x [ l ]
If l is present, x axis is logarithmic. Next 1 (or 2) arguments
are lower (and upper) x limits. Third argument, if present, is
grid spacing on x axis. Normally these quantities are deter‐
mined automatically.
-y [ l ]
Similarly for y.
-e Make automatically determined x and y scales equal.
-h Next argument is fraction of space for height.
-w Similarly for width.
-r Next argument is fraction of space to move right before plot‐
ting.
-u Similarly to move up before plotting.
-t Transpose horizontal and vertical axes. (Option -a now applies
to the vertical axis.)
If a specified lower limit exceeds the upper limit, the axis is re‐
versed.
Spline is a filter that interpolates extra data in input suitable for
graph to make smoother-looking curves.
The following options are recognized, each as a separate argument.
-a as in graph
-x as in graph
-k The constant k used in the boundary value computation
(2nd deriv. at end) = k*(2nd deriv. next to end)
is set by the next argument. (Default k = 0.)
-n Space output points so that approximately n intervals occur be‐
tween the lower and upper x limits. (Default n = 100.)
-p Make output periodic, i.e. match derivatives at ends. First and
last input values should normally agree.
DIAGNOSTICS
When data is not strictly monotone in x, spline simply reproduces its
input.
SEE ALSO
plot(1), grap(1)
BUGS
In graph segments that run out of bounds are dropped, not windowed.
Logarithmic axes may not be reversed.
Option -e actually makes automatic limits, rather than automatic scal‐
ing, equal.
Spline quietly discards points after the first 1000.
Spline's piecewise cubic fit (R. W. Hamming, Numerical Methods for Sci‐
entists and Engineers, 2nd ed., p. 349) overshoots at sudden jumps.
GRAPH(1)