to quickly customize the lines appearance in a plot
The LineSpec
is an optional argument
that can be used inside a plot
command to customize each new line aspect. It has to
be given as a concatenated string containing information
about color, line style or markers. It is very useful to
quickly specify such basic line properties.
To specify a red longdash-dot with diamond marker, the
string can be 'r-.diam'
. As you can
see, a full complete spelling of each property value is
not required but the string, which is a concatenation
(in any order) of these three types of properties, must
remain unambiguous. Furthermore, the string specification
is not case sensitive.
Here is a complete list of the LineSpec
types you can specify (using plot).
a string defining the line style. This property is linked to the
object's line_style
property (see
polyline properties).
Specifier |
Line Style |
- |
Solid line (default) |
-- |
Dashed line |
: |
Dotted line |
-. |
Dash-dotted line |
a string defining the line color. This property is linked to the
object's foreground
property (see
polyline properties).
Specifier |
Color |
r |
Red |
g |
Green |
b |
Blue |
c |
Cyan |
m |
Magenta |
y |
Yellow |
k |
Black |
w |
White |
A default color table is used to color plotted curves if you do
not specify a color (neither with LineSpec
nor with
GlobalProperty). When drawing
multiple lines, the plot command automatically cycles through
this table. Here are the used colors:
R |
G |
B |
0. | 0. | 1. |
0. | 0.5 | 0. |
1. | 0. | 0. |
0. | 0.75 | 0.75 |
0.75 | 0. | 0.75 |
0.75 | 0.75 | 0. |
0.25 | 0.25 | 0.25 |
A string defining the marker type. Note that if you specify a
marker without a line style, only the marker is drawn. This property
is linked to the object's mark_style
and
mark_mode
properties (see
polyline properties).
Specifier |
Marker Type |
+ |
Plus sign |
o |
Circle |
* |
Asterisk |
. |
Point |
x |
Cross |
'square' or
's' |
Square |
'diamond' or
'd' |
Diamond |
^ |
Upward-pointing triangle |
v |
Downward-pointing triangle |
> |
Right-pointing triangle |
< |
Left-pointing triangle |
'pentagram' or 'p' |
Five-pointed star (pentagram) |
No marker (default) |
clf(); x=1:0.1:10; // Init. plot(x,sin(x),'r-.>') // plots a dash-dotted line with a right-pointing triangle centered on each points. | ![]() | ![]() |
clf(); x=1:0.1:10; // If you specify a marker without a line style, only the marker is drawn plot(x,sin(x),'d') | ![]() | ![]() |
clf(); x = 1:0.5:10; // Init. // The order of information about color, line style or markers does not matter // BUT the information must be unambiguous subplot(311);plot(x,sin(x),'.b-'); subplot(312);plot(x,sin(x),'b.-'); subplot(313);plot(x,sin(x),'b-.');// The point belongs to information about line style (not marker!) | ![]() | ![]() |
//multiple plots with different LineSpecs clf(); t=0:%pi/20:2*%pi; plot(t,sin(t),'ro-.',t,cos(t),'cya+',t,abs(sin(t)),'--mo') | ![]() | ![]() |