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Before you display graphics you have to calculate coordinates - unlike
some other programs you can't just print sin(x) and give a range.
Typically you'd do something like the following
x=linspace(0, pi, 100);
y=sin(x);
plot(x,y);
The linspace command creates a vector of 100 elements equally
spaced between 0 and pi inclusive.
Once you have a graph it's easy to add titles - use the menus on the
graphics window or type
commands like
title('Trig');
xlabel('Radians');
ylabel('Sin');
You can plot more than one function on a graph. If you use hold on
before doing another plot, the first plot won't be erased. Alternatively,
you can give the plot command 2 lines at once.
The advantage of this approach is that the lines are automatically drawn
in different colours and that legends are easily created - e.g.
x=linspace(0, pi, 100);
y=sin(x);
y2=cos(x);
plot(x,y,x,y2);
legend('Sin','Cos');
Adding a grid is easy - use grid on. The menu options let
you change many features of graphs, but you can also use the axis
command to change many axis features - range, aspect ratio, etc.
The plot command has many options to control colour, markers, etc.
There's also scatter, bar, pie, stairs,
stem, polar, compass, etc. Type help graph2d or (if you want to see some graphics!)
see the Graphics tutorial
Note that you can have many figure windows open (read about the
figure command). You can also have many graphs in each figure.
The subplot command creates axes in tiled positions. So for
example if you want 3 rows each containing 2 graphs, and you want to
plot vector x in the bottom left graph (the 4th graph,
counting left-to-right), you type
subplot(3,2,4);
plot(x);
Use clf to clear the current figure.
Next: 3D plots
Up: Graphics
Previous: Graphics
