<A NAME=PLOT>
<TITLE>PLOT</TITLE></A>
<b><a href=r37_idx.html>INDEX</a></b><p><p>
<B>PLOT</B> _ _ _ _ _ _ _ _ _ _ _ _ <B>command</B><P>
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The command <em>plot</em> is the main entry for drawing a
picture from inside REDUCE.
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<P> <H3>
syntax: </H3>
<em>plot</em>(<spec>,<spec>,...)
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where <spec> is a <function>, a <range> or an <option>.
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<function>:
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- an expression depending
on one unknown (e.g. <em>sin(x)</em> or two unknowns (e.g.
<em>sin(x+y)</em>,
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- an equation with a function on its right-hand
side and a single name on its left-hand side (e.g.
<em>z=sin(x+y)</em> where the name on the left-hand side specifies
the dependent variable.
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- a list of functions:
if in 2 dimensions the picture should have more than one
curve the expressions can be given as list (e.g. <em>{sin(x),cos(x)}</em>).
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- an equation with zero left or right hand side describing
an implicit curve in two dimensions (e.g. <em>x**3+x*y**3-9x=0</em>).
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- a point set: the graph can be given
as point set in 2 dimensions or a
<A HREF=r37_0550.html>pointset</A> or pointset list
in 3 dimensions.
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<range>:
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Each dependent and independent variable can be limited
to an interval by an equation where the left-hand side specifies
the variable and the right-hand side defines the
<A HREF=r37_0422.html>interval</A>,
e.g. <em>x=( -3 .. 5)</em>.
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If omitted the independent variables
range from -10 to 10 and the dependent variable is limited only
by the precision of the IEEE floating point arithmetic.
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<option>:
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An option can be an equation equating a variable
and a value (in general a string), or a keyword(GNUPLOT switch).
These have to be included in the gnuplot command arguments directly.
Strings have to be enclosed in
string quotes (see
<A HREF=r37_0003.html>string</A>). Available options are:
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<A HREF=r37_0553.html>title</A>: assign a heading (default: empty)
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<A HREF=r37_0554.html>xlabel</A>: set label for the x axis
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<A HREF=r37_0555.html>ylabel</A>: set label for the y axis
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<A HREF=r37_0556.html>zlabel</A>: set label for the z axis
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<A HREF=r37_0557.html>terminal</A>: select an output device
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<A HREF=r37_0558.html>size</A>: rescale the picture
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<A HREF=r37_0559.html>view</A>: set a viewpoint
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<em>(no)</em>
<A HREF=r37_0560.html>contour</A>: 3d: add contour lines
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<em>(no)</em>
<A HREF=r37_0561.html>surface</A>: 3d: draw surface (default: yes)
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<em>(no)</em>
<A HREF=r37_0562.html>hidden3d</A>: 3d: remove hidden lines (default: no)
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examples: </H3>
<P><PRE><TT>
plot(cos x);
plot(s=sin phi,phi=(-3 .. 3));
plot(sin phi,cos phi,phi=(-3 .. 3));
plot (cos sqrt(x**2 + y**2),x=(-3 .. 3),y=(-3 .. 3),hidden3d);
plot {{0,0},{0,1},{1,1},{0,0},{1,0},{0,1},{0.5,1.5},{1,1},{1,0}};
on rounded;
w:=for j:=1:200 collect {1/j*sin j,1/j*cos j,j/200}$
plot w;
</TT></PRE><P>Additional control of the <em>plot</em> operation:
<A HREF=r37_0564.html>plotrefine</A>,
<A HREF=r37_0565.html>plot_xmesh</A>,
<A HREF=r37_0566.html>plot_ymesh</A>,
<A HREF=r37_0568.html>trplot</A>,
<A HREF=r37_0563.html>plotkeep</A>,
<A HREF=r37_0567.html>show_grid</A>.
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