Function plotq(x1,y1,stylestr1,stylestruct1)
plotq(x1,y1,stylestr1,stylestruct1,
x2,y2,stylestr2,stylestruct2, ...)
is an alternative for plot(x1,y1,style1, x2,y2,style2, ...),
but has some extra features:
-- limitation of the number of plotted markers;
-- step-wise lines.
Input arguments xK and yK are vectors, xK has the same length
as its companion yK.
Input arguments stylestrK hold a string with a code for
colour, line style and/or marker (see the remarks on "fmt"
in the help text of plot()). If it contains no information
on colour, a colour is automatically chosen. If it contains
no information on line style, no line is drawn. If it
contains no information on marker, no markers are drawn.
Instead and partly in addition to stylestrK, an Octave
structure stylestructK is included as input arguments.
It may have the following fields:
.colour containing a character or a rgb vector
.line containing a character
.step containing 0 or 1
.marker containing a character
.markerskip containing an integer >= 0
.markernumber containing an integer >= 0
The characters used for colour, line style and marker
are the same as in stylestrK. If markernumber == 0,
markerskip is used; if markernumber >= 1, markernumber
is used.
Information on line style, colour and marker from stylestrK
has priority over information from stylestructK.
Note that an empty string "" for stylestrK means that no
line and no markers are drawn. If stylestrK should be
ignored, put an empty matrix [] on its place.
Note on using colour numbers in stylestrK: it seems that
line colour 6 results into white as a real rgb vector; only
line colours 0 to 5 result into colour characters "k", "r",
"g", "b", "m", "c", respectively.
Therefore, it is better to input colour characters directly:
"k", "r", "g", "b", "y", "m", "c", "w". See also the help on
plot().
Function plotq() internally calls the standard Octave
function plot().
Note that plotq() behaves in the same way as plot()
for NaN, NA, Inf and -Inf values for xK and yK, i.e.
a line is broken at such a point, and a marker is not
drawn at such a point.
(c) 2026 fabien van mook
2026.08.20 release of this file within package "fvm-miscellaneous" under GNU GPLv3+
