functions in graph.i - t
triangle= plotting keyword
sets the triangulation array for a contour plot. The triangulation
array must be the same shape as the IREG (region number) array, and
the correspondence between mesh zones and indices is the same as
for IREG. The triangulation array is used to resolve the ambiguity
in saddle zones, in which the function Z being contoured has two
diagonally opposite corners high, and the other two corners low.
The triangulation array element for a zone is 0 if the algorithm is
to choose a triangulation, based on the curvature of the first
contour to enter the zone. If zone (i,j) is to be triangulated
from point (i-1,j-1) to point (i,j), then TRIANGLE(i,j)=1,
while if it is to be triangulated from (i-1,j) to (i,j-1), then
TRIANGLE(i,j)=-1. Contours will never cross this "triangulation
You should rarely need to fiddle with the traingulation array;
it is a hedge for dealing with pathological cases.
PLOTTING COMMANDS: plc
keyword, defined at i0/graph.i line 1029
type= plotting keyword
selects line type. Valid values are the strings "solid", "dash",
"dot", "dashdot", "dashdotdot", and "none". The "none" value
causes the line to be plotted as a polymarker. You should also
check the plmk function if you need polymarkers.
The type value may also be a number; 0 is "none", 1 is "solid",
2 is "dash", 3 is "dot", 4 is "dashdot", and 5 is "dashdotdot".
PLOTTING COMMANDS: plg, plm, plc, pldj
keyword, defined at i0/graph.i line 828